WASHINGTON, March 3 -- The U.S. Department of Justice (DOJ) has concluded in its investigation report that a widespread discrimination against the black communities existed among police forces and other law enforcement officials in Ferguson, Missouri, U.S. media said on Tuesday.

The New York Times reported that law enforcement officials familiar with the DOJ report, expected to be released within this week, said the report accused the officers of using excessive force and making unjustified traffic stops for years.

The report also pointed out that discrimination against the black communities was caused by racial stereotypes held by white police officers.

The DOJ began its civil rights investigation after white officer Darren Wilson shot to death an armed black man Michael Brown in August. Later, a local grand jury declined to indict Wilson.

According to The New York Times, a separate DOJ report was expected to clear Wilson of any civil rights violations in the deadly shooting of Brown.

A panel on policing reform appointed by U.S. President Barack Obama said on Monday in its interim report that deadly police shootings should be investigated by independent prosecutors and data on officer-involved shootings should be collected.

It also urged the federal government to support the development of new "less than lethal" technology to help control combative suspects and decrease the number of fatal police interventions.

"The fatal shootings in Ferguson, Cleveland, and elsewhere have put the consequences of use of force front and center in the national news. Policies and procedures must change, but so should the weaponry," said the report.

Widespread of protests erupted last year after local grand juries declined to indict police officers involved in the deadly shooting of Brown in Ferguson and the chocking death of Eric Garner on Staten Island in New York City.

In his first public discussion after the Ferguson and New York City incidents raised heated debates in recent months, U.S. Federal Bureau of Investigation (FBI) Director James Comey acknowledged on Feb. 12 that the U.S. society is "at a crossroads" on racial relations.