Four gunmen shoot 11 police officers - killing at least five - and 'leave bombs all over the place' during Dallas protests

Four gunman have shot 11 police officers - killing at least five - and may have planted a bombs 'all over' downtown Dallas.

One of the police officers killed in the attack has been identified as 43-year-old Dart Officer Brent Thompson.

The shooters opened fire from 'elevated positions' in a coordinated attack, picking off officers 'ambush style' as they manned a protest over the deaths of two black men, police chief David Brown said.

Three of them are in custody. A fourth man who was engaged in a shootout with police has reportedly killed himself with a shot to the head, Fox 4 TV Dallas reports. The gunman, who was holed up in a parking garage, told officers bombs have been planted across Dallas and that 'the end is coming'.

‘We have in custody a female who was in the same area as the El Centro garage,' Brown said.

'The suspect that we are negotiating with has told our negotiators “the end is coming”, and he is going to hurt and kill more of us and that there are bombs all over the place in the garage and downtown.

‘We still don’t have complete comfort level that we have all the suspects.’

Officers found a suspicious package near where one of the gunmen was caught and a bomb squad are dealing with it.

A gruesome video shows a heroic policeman taking on one of gunmen, but being gunned down by the shooter before being shot again execution-style, from point-blank range.

Police said two people are being questioned after they were spotted speeding away from the scene of the shooting in a black Mercedes. An officer saw one of the pair hurriedly putting a camouflage bag in the back of the car before driving off 'at a high rate of speed'.

A fourth suspect named as Mark Hughes, who was pictured walking through Dallas with what appeared to be an assault rifle, has been released from custody after he turned himself into police when cops made a public appeal and his family said he was an innocent bystander.

Mr Hughes said he was released from police custody after a 30 minute interrogation. The shocked ‘bystander’ told KTVT: 'I can't believe it. The crazy thing about it was I was down here, I couldn't get to my vehicle because of the roadblock and at hindsight 20/20 I could easily have been shot.’

Mr Hughes was unaware that his face was being plastered over the internet as a suspect in the shooting. 

The two snipers opened fire from 'elevated positions', picking off officers as they manned the demonstration in downtown Dallas on Thursday evening, police chief David Brown said.

Pictured is a man named as Mark Hughes, who was pictured walking through Dallas with what appeared to be an assault rifle. He turned himself into police after cops made a public appeal and has now been released from custody.

The shooting started at 8.45pm as hundreds of protesters marched through Dallas demanding justice for two black men shot dead by police earlier this week.

'I didn't know. We received a phone call that my face was on there as a suspect and immediately I flagged down a police officer,’ Mr Hughes said.

'I was talking to police laughing and joking with police officers,’ he added.

During his 30 minute interrogation Mr Hughes claimed officers ‘lied’ and said the had video of him shooting and that they had witnesses ‘saying I shot a gun’.

‘At the end of the day the system was trying to get me,’ he claimed.

Mr Hughes said he has not yet received an apology

'Now you have my face on national news are you going to come out and say this young man had nothing to do with it?,’ he asked.

'We've been getting death threats. All I know is there was nothing just going on and there was a persecution on me unrightly and they need to do something about it.’

Five police officers have died and as many as three others are in a critical condition. A female member of the public was also shot.

The DART officer killed, Brent Thompson, joined the department in 2009 and is the first officer to be killed in the line of duty since 1989 when DART formed a police department.

Morgan Lyons, a spokesman for DART, said: 'As you can imagine, our hearts are broken.'

'This is something that touches every part of our organization. We have received countless expressions of support and sympathy from around the world through the evening. We are grateful for every message. Thank you.'

It is not known if the shooters were protesters, however they appear to have been militarily trained. Their motive is not clear.

'Our worst nightmare has happened,' Dallas Mayor Mike Rawlings said. 'It is a heartbreaking moment for the city of Dallas.'

The shooting started at 8.45pm as hundreds of protesters marched through Dallas demanding justice for two black men shot dead by police earlier this week.

Horrifying footage shows peaceful protesters chanting 'hands up, don't shoot' before suddenly scattering as shots were fired near Belo Garden Park.

Another video captures semi-automatic gunfire ringing out, with dozens of shots heard as people scream and run for cover.

One of the alleged shooters - wearing tactical gear and a bulletproof vest - was hunkered down in a garage earlier on Thursday evening and engaged cops in a shootout before he was detained, a police source told Fox 4.

A horrific video taken on a cell phone by a terrified Dallas resident shows a heroic policeman trying to shoot one of the gunmen.

The officer is seen ducking behind a pillar but being shot by the gunman, who then stands over the cop and pumps another bullet into him.

Police Chief Brown said that it appeared the shooters 'planned to injure and kill as many officers as they could'. 

The suspects 'have threatened to plant a bomb in the downtown area', Brown added.

An image of Mr Hughes was released by Dallas Police showing him walk through the city carrying what appeared to be an assault rifle and wearing a camouflage shirt. The force tweeted: 'Please help us find him!'

However, a video shows the black man wandering among panicked protesters moments after gunfire erupted and he is not shooting. His brother tweeted that he was not involved in the shooting and had taken himself to a police station after Dallas Police released his picture. Mr Hughes has now been released.

A man who is believed to have been a protester - and not involved in the shooting - was arrested shortly after the shooting.

Officers were also seen stopping a man at gunpoint from leaving downtown Dallas in a white SUV.

One of the injured police officers has been named as Misty McBride. The transit officer, who is a mother, was reportedly shot in the shoulder but will survive.

A member of the public, mother-of-four Shetamia Taylor, was shot in the calf as she shielded her children, hiding her 15-year-old son under a car.

The rest of the killed and injured are yet to be identified. 

Police found a suspicious package near where the alleged gunman was caught and a bomb squad are dealing with it. Pictured, police responding to gunshots.

Flights are being re-routed around Dallas overnight, the FAA said, and delays and cancellations from local airports are expected.

Most of downtown Dallas is expected to be closed down tomorrow, with workers warned to ensure their offices are open before heading into the city.

Texas Governor Greg Abbott offered 'whatever assistance the City of Dallas needs at this time'.

'In times like this we must remember - and emphasize - the importance of uniting as Americans,' he said.

The search for the gunmen stretched throughout downtown, an area of hotels, restaurants, businesses and some residential apartments. The scene was chaotic, with helicopters hovering overhead and officers with automatic rifles on the street corners.

'Everyone just started running,' Devante Odom, 21, told The Dallas Morning News. 'We lost touch with two of our friends just trying to get out of there.'

Carlos Harris, who lives downtown, told the newspaper that the shooters 'were strategic. It was tap tap pause. Tap tap pause'.

Hundreds of people had marched through Dallas peacefully earlier on Thursday, demanding justice for Alton Sterling and Philando Castile, who were shot dead by police.

Police officers were seen shielding bystanders as they tried to evacuate the streets.

The shootings came as th ousands of people attended demonstrations against police brutality across America, with marches taking place in New York, Atlanta, Philadelphia, Chicago and Washington DC, as well as in Louisiana and Minnesota - where Sterling and Castile were killed. 

Hundreds of people had marched through Dallas peacefully earlier on Thursday, demanding justice for Alton Sterling and Philando Castile, who were shot dead by police.