People attend a candlelit vigil to mourn the victims of Manchester terror attack at Albert Square in Manchester, Britain on May 23, 2017. On Monday night, a suicide terror attack took place at Manchester Arena at the end of a pop concert, killing at least 22 people, several of whom were children, while injuring 59 others. (Xinhua/Han Yan)

LONDON, May 25 (Xinhua) -- Police hunting a potential terror gang behind have found items significant to the probe into the Manchester Arena bombing, it was revealed Thursday.

Greater Manchester Chief Constable Ian Hopkins described the on going investigation as fast moving as detectives continued to quiz eight suspects following the terror bombing at the Manchester Arena.

He said: "This continues to be a fast-moving investigation and there has been a significant amount of activity taking place."

Police are working in the search for accomplices of suicide bomber Salman Abedi alongside specialist national counter terrorist officers as well as UK intelligence services, said Hopkins.

Hopkins added: "The arrests that we have made are significant, and initial searches of premises have revealed items that we believe are very important to the investigation."

Hopkins did not elaborate on what police had discovered in the searches of homes and properties linked to those arrested.

In the latest development Thursday night police revealed they found potentially suspicious items during a raid in a house in Wigan in Greater Manchester. One of the eight men still being held was arrested in Wigan.

Police placed a large cordon around the house and evacuated families from nearby homes as an army bomb disposal team were drafted in. People told local media they had seen soldiers using a remote robot close to the property.

Greater Manchester Police said in a statement: "A house in Wigan was raided and is currently being searched. Potentially suspicious items were found at the address and a large cordon has been put in place.

"We have a number of officers on the ground and are evacuating people as a matter of precaution as public safety is paramount to our investigation."

Media reports in London said Thursday that investigators believed there may be more people at large who are part of a terror network linked to the Manchester Arena attack. It raised fears that more bomb-making materials still have to be found.

Theresa May said Britain's terror threat would remain at critical, indicating a terror attack was imminent.

Other sources quoted in the media raised the fear some members of a terror network may be in hiding.

In another response to Monday's attack, armed police officers are being deployed for the first time patrolling trains nationwide, British Transport Police announced.

Passengers on London Underground have become accustomed to seeing armed police on the Tube for some months, but until now they have not patrolled the national rail network.

As the round the clock hunt for more people linked to terrorism continued, people across the country stood in a minute's silence in tribute to the 22 adults and children killed, and the 116 injured.

Queen Elizabeth also traveled to Manchester to speak with young victims being treated at the Royal Manchester Children's Hospital. Talking to doctors and nurses, the Queen described the attack at the end of a pop concert as "wicked".