A domestic argument that turned violent sent an 18-year-old man to the hospital in critical condition and left a 20-year-old Waimanalo woman under arrest in a police cellblock for suspicion of attempted murder, police said.

The woman used a "dangerous instrument" to injure her boyfriend at about 2:40 p.m. yesterday in Kailua, police said. An ambulance took the man to the hospital in critical condition with unspecified injuries.

Officers arrested the woman at 2:50 p.m. at Kailua District Park. Police said the couple have an infant child