Two FDNY siblings were arrested in a large clash at a Brooklyn park early Sunday, police said.

They were at the scene when cops went to Herbert Von King Park in Bedford-Stuyvesant about 12:20 a.m. for a report of a large disorderly crowd at Van Buren Street and Tompkins Avenue, authorities said. A 47-year-old man was found at the scene with slashes from a box cutter on his head and torso, and was taken to Kings County Hospital for treatment.

A 22-year-old was also found struck in the head from a wooden stick, according to police officials. When cops arrested his alleged assailant Kenshawn Felton, 20 , FDNY medic Janice Gardner, 35 allegedly punched one of the officers twice.

Her firefighter brother Aaron Gardner, 36, then allegedly then tried to pummel a cop.

Both siblings were arrested, authorities said. Police charged the sister, Janice, with resisting arrest and obstructing governmental administration. Her brother Aaron was accused of attempted assault, resisting arrest, and obstructing governmental administration, authorities added.

Another man and woman at the scene were also given summonses for disorderly conduct. The assailant who injured the man with the box cutter has yet to be caught.

The relationship between the FDNY siblings and Felton was not immediately clear. The clash started over a perceived gesture towards a girl, police officials said.

Three cops suffered minor injuries during the melee.