Dorchester shooting is Boston’s first homicide of the year; police seeking public’s help

Police officers stood guard tonight at the scene of Boston’s first killing of the year — a Dorchester residence where a man in his 20s was found shot to death yesterday afternoon.

Authorities did not release the identity of the man, but said the investigation into his death is active and ongoing.

“We’re still asking for the public’s help,’’ said Officer Nicole Grant, a police spokeswoman.

Police said officers responded to 23 Trull St. after receiving a call for shots fired at about 1:53 p.m. yesterday.

A man in his 20s suffering from life-threatening injuries from a gunshot wound was found inside the two-and-a-half story residence and taken to Boston Medical Center, where he was later pronounced dead.

Police spokesman Officer Eddy Chrispin declined to provide further details tonight.

A neighbor, who requested that she not be named because she fears for her safety, said she saw the victim lying face-up with gunshots to his abdomen.

She said police officers attempted to resuscitate the man, but to no avail.

“They climbed on top of him to do CPR,’’ said the woman. “He didn’t move. He was limp. It’s sad.’’

Homicide detectives investigated the scene into the evening and both 23 and an adjacent residence at 21 Trull St. were closed off from the sidewalk with caution tape.

After the police tape has been cut, both marked and unmarked cruisers remained parked outside the home along Trull Street and around the corner on Glen Street, which 21 Trull St. abuts, until at least 9 p.m.

Officers at the scene said they were there to wait for the properties’ tenants to return after the initial indoor crime investigation had been completed and would not allow anyone but those who lived there from trying to approach either residence.

Last April, 23-year-old Edmund “Duce’’ Andrade was fatally shot in the head across the street, at 22 Trull St., according to police.

Andrade was known to have sold drugs a neighbor and former gang member told the Globe at Andrade’s funeral last year.

Boston Police asked anyone with information to call the Homicide Unit at 617-343-4470. Information can also be provided anonymously to police via the CrimeStoppers Tip Line at -800-494-TIPS or by texting the word ‘TIP’ to CRIME (27463).