The man being hunted by police in connection with a quadruple homicide on Monday night is now suspected in the death of a fifth man on Tuesday.

Officials said Pablo Serrano-Vitorino, who may be armed with an AK-47, may be responsible for the shooting death of a 49-year-old Missouri man in his Montgomery County home, ABC17 reported. The murder occurred near where Serrano-Vitorino abandoned his pickup truck.

Montgomery County schools were on lockdown Tuesday.

Officials said Serrano-Vitorino, 36, was a neighbor of the four men shot and killed on Monday, according to FOX4. Authorities said he was believed to be at the Kansas City, Kan. house when the shooting unfolded.

Three men were dead when police arrived at the residence around 11 p.m. Monday, and a fourth, found on the porch, died later from his injuries. One of the men was able to place the initial phone call to police. The identities of those killed have not been released.

Cops found Serrano-Vitorino’s red 2002 Dodge Ram 1500 pickup truck abandoned in Missouri on Tuesday, shortly before discovering the body of the Montgomery County man.

Serrano-Vitorino was in Wyandotte County Jail in June 2015 for alleged domestic battery, a Wyandotte County Sheriff’s Office spokesperson told FOX4.

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