Updated

City officials were on alert Wednesday and extra officers were on standby in anticipation of a decision by a grand jury on the blaze of police gunfire that killed an unarmed man on his wedding day and wounded two of his friends.

All five officers involved in the shooting, in which 50 shots were fired, were called before the grand jury last week.

The shooting raised questions about police tactics and prompted vigils and protests by civil rights activists; the slain man and his friends were black; some of the officers are black and some are white.

Friends and relatives of Sean Bell, the man who died, planned to gather with the Rev. Al Sharpton in case the grand jury's decision on charges were announced. Bell's relatives have called for prosecution of the five officers.

"If there are no indictments, there will be certain levels of protests and visible actions to show why the community is outraged," Sharpton said in an interview Tuesday. He added that he expected those events to be peaceful.

The grand jury could consider charges ranging from assault or reckless endangerment to second-degree murder, or they could find that the officers were "reasonably justified" in the shooting. Under state law, police can use deadly force if they have a "reasonable" belief that their lives or those of civilians are in immediate danger, even if they were wrong.

Extra police officers were on standby, and Mayor Michael Bloomberg on Tuesday met with black leaders in the Queens neighborhood where Bell was killed in November.

The mayor's meeting was part of an outreach campaign that began just after the shooting and went into overdrive this week as three months of presentations to the grand jury wound down.

He has urged that the city stand united and stay peaceful no matter what the outcome.

"With an exception of probably a handful of hotheads, we understand we all have to work together, live together, and we're going to make this work," Bloomberg said. "The Police Department will in fact do what they're supposed to do and make sure that the streets are as safe after an indictment or no indictment — whatever the case may be — as they were before."

Bell and his friends, Trent Benefield and Joseph Guzman, had been celebrating at the Kalua strip club the night before he was to be married.

Police were at the club as part of an undercover operation in response to complaints about prostitution. Union representatives and lawyers for the officers have said the five became convinced that Bell and his friends were going to retrieve a gun from a parked car after overhearing them argue with another patron.

When one officer approached the car, driven by Bell, the vehicle lurched forward and bumped him, then twice rammed into an unmarked police minivan, the department said. The undercover detective has claimed through his lawyer that he saw one of the men in the car make a suspicious move, which set off the shooting.

Benefield, Guzman and other members of the bachelor party have said the officers fired without warning.