UPDATE (12:40 a.m.) Police have fired tear gas into the home in an effort to get the man out, according to Monrovia Police Chief Jim Hunt. They established communication earlier but were unable to get him to surrender, Hunt said. An apartment building across the street from the house was evacuated and the Red Cross is assisting those displaced, Hunt said.
UPDATE (12:28 a.m.) The man remains barricaded inside his home, according to Monrovia Police Sgt. Michael Head.
UPDATE (9:19 p.m.) Police have fired multiple flash-bang grenades over the last few hours in attempts to make contact with the suspect, Monrovia Police Captain Alan Sanvictores said.
"We have set off distracting devices to try and gain his attention," he said.
Police have "preliminary indications" that the man may be suicidal, Sanvictores said. They were notified that he was armed and acting erratically by family members, he said.
"Our concern here is his safety as well as everyone else in the area," Sanvictores said.
The man is holed up in a house on the corner of Duarte Road and Encino Avenue by himself, though other family members live with him. They are cooperating with police in the investigation, Sanvictores said.
Police were able to make initial contact with the man but he has not communicated with investigators for several hours, according to Sanvictores. It is unknown if he has fallen asleep or is intoxicated, he said.
Police will continue to wait for the man to make contact, Sanvictores said.
"We react to whatever situation is presented to us," he said. "For us it's a waiting game."
UPDATE (8:24 p.m.) A loud blast could be heard outside the scene at about 8:15 p.m. Spotlight shining on building, police talking to suspect through loudspeaker: "We have your house surrounded. Come out and talk to us."
PREVIOUSLY: An armed man has barricaded himself inside a home on Duarte Road and police have deployed a SWAT team and crisis negotiator to try and get the man to surrender.
Residents in a home in the 800 block of West Duarte Avenue called police at about 3 p.m. to alert police that they were concerned about the well-being of a man inside the home. The man remains inside the home alone and has made threats, according to Monrovia Police Lt. Michael Lee.
"He's made some threats, that's whay we have such a presence there," Lee said.
SWAT members and an armored vehicle could be seen in the street outside the apartment building on Duarte Rd. Traffic is blocked off on the street between 6th and 8th Avenues.
The Foothill Special Enforcement Team (F-SET) has responded to the scene, Lee said. Based on the statements of the man, Lee said he expected the situation to drag on for some time.
"Right now we're taking the lowest key approach, which is talk and wait and talk and wait and see what we can get out of this," Lee said.
Monrovia Police Chief Jim Hunt said police are "waiting him out" in an effort to end the standoff without violence. He would not comment on what the man was upset about.
Police set up a command post at nearby Camino Grove Elementary in Arcadia. Units from Glendora, Irwindale, Arcadia, La Verne and Baldwin Park responded to the incident.
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