A 44-year-old man was arrested Tuesday night in Kalihi after allegedly stabbing his girlfriend’s 17-year-old son, who was also arrested for allegedly assaulting a paramedic who was treating him, Honolulu police said.

At about 10:45 p.m., patrol officers responded to a Rose Street residence where an argument between the man and his girlfriend had escalated after the teen confronted the suspect, according to a Honolulu Police Department news release. The suspect stabbed the teen during the altercation, according to HPD.

Honolulu Emergency Medical Services responded and, while EMS personnel were treating the teen, “the victim became combative and assaulted an EMS worker,” HPD said.

The teen was taken to a hospital in serious condition where he was arrested for suspicion of second-degree assault. Officers arrested the 44-year-old man for suspicion of second-degree attempted murder, HPD said.

An EMS spokesperson said the emergency medical technician was in stable condition.