Nearly two months after Sean Bell was fatally shot by police outside a Queens strip club, a grand jury began hearing evidence yesterday that could illuminate certain facts of the case for the first time.

Meanwhile, a group of Bell’s friends and relatives took up a vigil outside Queens Criminal Court, where the proceedings could take a month or longer, attorneys involved in the case said.

While few details emerged from the closed-door proceedings yesterday, attorneys representing Bell’s family, who met with Queens prosecutors this past Thursday, said prosecutors will call at least 40 witnesses. If they are called to testify, the five officers involved in the November 25 shooting would testify last, the attorneys said.

A spokesman for District Attorney Richard Brown of Queens declined to comment on the status of the grand jury. “The grand jury is a secret,” the spokesman, Kevin Ryan, said.

An attorney for two men who were with Bell outside Kalua Cabaret, Trent Benefield and Joseph Guzman, said his clients would testify. “Our clients are ready, willing, and able to testify,” the attorney, Sanford Rubenstein, said.

Mr. Mitchell said his meeting with prosecutors raised questions about how they are handling the case, which he said has already taken too long. He said he plans to write a letter to Governor Spitzer in which he will reiterate his call for a special prosecutor to be appointed.

Mr. Mitchell also said he was concerned that Detective Michael Oliver, who allegedly fired 31 times, would be targeted by prosecutors while the other officers would go free. “Our position is, even if you fired one shot … you should be prosecuted,” he said.

His sentiment was echoed by a group of Bell’s relatives and friends, who wore placards with Bell’s photograph and the words “Never Again.”

“We are here to make sure Sean Bell never gets out of the eye of the public so that this never happens again to anybody’s family,” Bell’s uncle, Al Walker, said.