A gunfight at a bar on the outskirts of Miami left two people dead and seven injured early Saturday, with the wounded including an off-duty police officer and six bystanders.

The bloodshed began when a fight erupted around 3:30 a.m. at Martini Bar in the Miami suburb of Doral, authorities said.

When a security guard tried to intervene, an unidentified man pulled out a gun and fatally shot the security guard, Miami-Dade Police Detective Alvaro Zabaleta reportedly said.

Two off-duty Doral police officers who were working security fired back with shots of their own, ultimately striking and killing the shooter, officials said.

One of the officers, a four-year veteran of the force, was shot in the leg, said Chief Edwin Lopez. He was released later Saturday.

In the exchange of fire, six bystanders — five men and a woman — were also hit, according to the Associated Press. 

The woman and one of the men were hospitalized in critical condition, according to NBC Miami.

Zabaleta told reporters Saturday that it was too early to know "who shot who." 

A nearby resident told WPLG-TV that he heard a burst of gunfire ring out.

"Around 3:15 or 3:30 in the morning, I heard three initial gunshots," said William Suedois. 

"I didn't really know where it was coming from. I thought it was fireworks. Then I heard probably 10 or 15 directly after that — very, very fast and very loud. It was very scary — very scary."

The Florida Department of Law Enforcement is investigating the shootings, as Miami-Dade police focus on the two deaths. 

Officers continued to interview witnesses into the early morning on Saturday, and parts of the mall remained roped off as crime scene technicians collected evidence. 

No clear reason has been given as to what prompted the fight.