SAN DIEGO—In what investigators believe was a murder and suicide, a man shot two women to death inside a home in Lakeside before turning the gun on himself, authorities said Dec. 31.

Deputies dispatched just before 11:30 p.m. Dec. 30 to a home in the 13500 block of Interstate 8 Business, on a radio call of an assault with a deadly weapon, made the discovery, said Lt. Chris Steffen of the San Diego County Sheriff’s Department.

“Upon arrival, deputies learned a male might have shot a female after an argument and both were believed to still be inside the residence,” Steffen said. “Upon making entry, deputies discovered two deceased females in their late 50s and a deceased male in his late 50s.”

Steffen said all three people appeared to have suffered fatal gunshot wounds, adding that the circumstances and motivations were under investigation.

The department’s homicide unit urged anyone with information about the shootings to call them at 858-285-6330, or after hours at 858-565-5200. Anonymous callers can contact Crime Stoppers at 888-580-8477.