MIAMI BEACH, Fla. -- The Miami Beach police chief is defending the actions of his officers in two fatal shootings that happened in June.

The Miami Beach police's internal affairs department and the state attorney's office continue to investigate the shooting death of 29-year-old Husien Shehada on June 14.

Surveillance video released Thursday shows Shehada and his brother, Samer, striding down Washington Avenue. Three men had beaten up Samer Shehada earlier in the evening, and police said the brothers were looking for the attackers, Local 10's Michael Putney reported.

In a freeze frame from the video, it appears that there is something beneath Husien Shehada's T-shirt. People who called 911 that night thought it was a gun.

"Two Hispanics walking down the block with T-shirts on, it looks like one of them has a machine gun on him," a 911 caller said.

Officer Adam Tavss and other police officers who arrived at the night club Twist early that morning were on edge because they thought the Shehada brothers were heavily armed.

"Be advised, they're saying the subject is carrying it in his left hand and the complainant saw the outline of the large gun underneath his white shirt," the dispatcher said in a call.

Tavss fatally shot Husien Shehada during a confrontation with the brothers.

But Husien Shehada was not carrying a gun. Police said he had reached underneath his shirt, and they opened fire.

"An unarmed man was killed. It's been contended by the police department that he may have, that they were looking for someone with an AK-47 or some type of huge assault rifle and they shoot a man with no weapons at all," said Shehada family attorney Gregory Samms.

The law allows a police officer to use deadly force if he believes his life is in danger. Miami Beach police said the officers thought Husien Shehada was reaching for a weapon and did not know he was unarmed.

Miami Beach Police Chief Carlos Noriega spoke publicly for the first time Thursday about a second shooting involving Tavss and other officers. In that case, a man pistol-whipped a cab driver and stole his taxi, taking off east in the westbound lanes of the MacArthur Causeway. The taxi thief got into a crash, and then police shot him at least nine times, killing him.

"The officers' actions in these cases, however, were based on the subjects' actions, the information they had at the time of the encounters, as well as their training and experience. It is important to note that the subjects in both cases had exhibited aggressive, violent, noncompliant and criminal behavior," Noriega said.

Noriega said investigators recovered a gun from Biscayne Bay three days after the shooting but they cannot definitively say it was the gun used by the taxi thief.