An NYPD plainclothes officer died late Tuesday night at a Harlem hospital after a suspect shot him in the head during a foot pursuit, Police Commissioner William Bratton said at a news conference where the officer was treated.

Bratton identified the slain officer as Randolph Holder, 33, a five-year veteran assigned to the housing bureau. He was pronounced dead at 10:22 p.m., Bratton said. Holder lived in Brooklyn, said an NYPD spokesman.

A suspect was in custody at another hospital after being wounded in an exchange of gunfire with police, Bratton said. NYPD spokesman Stephen Davis said the suspect's name will be released after he is expected to be charged later Wednesday.

Bratton said Holder, a native of Guyana who was unmarried, joined the NYPD in 2010 and came from a law enforcement family. His father and grandfather worked as police officers in Guyana, Bratton said.

"Tonight he did what every other officer in the NYPD does," Bratton said at Harlem Hospital Center, flanked by Mayor Bill de Blasio and other NYPD and city officials. "When the call comes, he ran towards danger and it was the last time he will respond to that call."

De Blasio appealed to New Yorkers to "offer prayers to his family who are experiencing unimaginable pain ... It's a sadness that is so hard to describe. We are fighting to understand."

Holder had been taken to Harlem Hospital Center in critical condition following the shooting, which occurred sometime after 8:30 p.m., the NYPD said.

Holder, assigned to Police Service Area 5 in Manhattan, was shot while pursuing a man with a gun from 103rd Street and the FDR Drive.

The unit patrols public housing in the area of the 23rd, 25th and 28th precincts.

Police recovered two firearms -- a semiautomatic handgun and a revolver -- at 120th Street and FDR Drive, officials said. Bratton said the suspect in Randolph's shooting was taken to NewYork-Presbyterian Hospital/Weill Cornell Medical Center in Manhattan with gunshot wounds. He remained at the hospital early Wednesday morning, but his condition was not released.

Just before 11 p.m. Tuesday, dozens of NYPD officers, both uniformed and plainclothes, gathered at the Harlem hospital waiting for an update on the wounded officer's condition.

Bratton and de Blasio announced Randolph's death at the news conference about 45 minutes later.

The FDR Drive remained closed early Wednesday morning from 96th Street to 125th Street as NYPD investigators to searched for evidence.

Bratton said Randolph was the fourth NYPD officer to be killed in the line of duty in less than a year.

In May, NYPD Officer Brian Moore, 25, of Massapequa, was shot in the head as he and a partner patrolled in Queens Village. Moore died two days later, and Demetrius Blackwell, of Queens Village, was charged with the Plainedge High School graduate's killing.

Days before Christmas in 2014, Officer Wenjian Liu, 32, and his partner, Rafael Ramos, 40, both of Brooklyn, were gunned down execution style in Bedford-Stuyvesant by a man who took his own life a short time later.

"Four police officers murdered in eleven months," Bratton said at the news conference. "That's about as bad as it gets."

With Anthony M. DeStefano