A brutal brawl between two groups of FDNY firefighters in the Bronx has sparked several investigations and sent shockwaves through the department’s leadership.

More than a dozen members pummeled three rivals with punches and kicks to the head, sources told the New York Post.

According to the Post, the tape shows Adam Soler, 35, of Engine 68, being held down by two firefighters from Rescue Co. 3 and repeatedly kicked by a third.

“It was one of the most severe beatings they’ve seen on tape,” an FDNY insider told the newspaper, recalling the reaction by brass who viewed video of the bloody fisticuffs.

“They can’t believe one of the guys wasn’t killed.”

“Someone grabbed his head and started pounding it into the pavement,” one said.

Another firefighter accidentally kicked a curb. In the video he’s reportedly seen grimacing and holding his foot, which may have been broken.

Soler suffered a concussion and has been on medical leave since the June 6 fracas.

Capt. Michael Nigro of Engine 68 became so upset watching a clip of his firefighters being beaten he ordered staffers to briefly pause it.

Nigro had to compose himself before coming back in to watch the rest of the brawl.

Still, two months after the June 6 incident, no one has been arrested or fired.

The FDNY identified six participants in addition to Soler, all of whom were suspended for one month but are now back on the payroll

“If they assaulted anyone, they shouldn’t be getting a paycheck,” one FDNY insider told the Post. “They should be getting a prison cell.”

The fracas marked another black eye for a department that has been plagued by violent clashes among its ranks.