Aug. 27—Pittsburgh's Department of Public Safety will review the use of force by a group of city police during their arrest of a man Downtown on Friday night, after multiple videos posted to social media brought criticism from community groups and others.

Police said the man, identified in a criminal complaint as Jashon Martin, 32, of Pittsburgh's Garfield neighborhood, was observed multiple times Friday during police surveillance along the Smithfield Street corridor and Mellon Square Park.

The surveillance was conducted in response to complaints about drug activity Downtown.

Police said they observed Martin make multiple drug transactions, according to court documents. They also saw him get into a scuffle with two other men before leaving the area and returning about 90 minutes later in different clothing with his right arm "pinned against his side and his right hand in front of his body, consistent with concealing a weapon on his person," police wrote in a criminal complaint.

Based on their surveillance, police attempted to detain Martin for a probable-cause search, and said he "immediately reached to the front waistband area of his body" and ignored commands to stop resisting, according to court documents. During the course of the arrest, Martin was taken to the ground and an officer delivered several closed-fist punches in order to stop him from reaching toward his front waistband, the criminal complaint reads.

After Martin was handcuffed, a search turned up a fixed-blade knife, several bags and containers of marijuana, a digital scale, plastic sandwich bags and two cellphones, according to the complaint.

Martin told police he wanted to see paramedics, but refused to speak with them when they arrived, police said.

Video posted to several social media platforms appears to show a group of officers holding Martin down to the ground as they attempt to handcuff him. At least one witness in the background calls out to police to "stop punching."

"The Gainey administration, the Department of Public Safety and city council are taking this encounter, and the considerable community concern it has generated, extremely seriously and are reviewing all available video footage and gathering as much information as possible pertaining to the incident," Pittsburgh public safety officials said in a statement released Saturday.

A letter signed by the Alliance for Police Accountability, the Pittsburgh branch of the NAACP and the Black Political Empowerment Project said all three groups are "deeply troubled" by the videos.

"The videos ... vividly depict a scene where the officers employed extreme and unjustifiable force, raising serious questions about the proportionality of their actions as well as violation of impeding the right of the public to video record," the letter reads.

The groups requested a meeting with the Pittsburgh Police Bureau's leadership to address the specifics of the incident.

The Pittsburgh Citizen Police Review Board is asking anyone who witnessed the incident to call 412-765-8023, email cprb@pittsburghpa.gov or see CPRBpgh.org.

Martin has three open arrest warrants, and was arraigned on charges of drug possession with intent to deliver, resisting arrest and aggravated assault. A Sept. 14 preliminary hearing is set in Judge Kim Berkeley Clark's Pittsburgh court.

Patrick Varine is a Tribune-Review staff writer. You can contact Patrick by email at pvarine@triblive.com or via Twitter .