St. Paul police were searching for one or more suspects late Saturday after an afternoon shooting in a multiunit building in the Payne-Phalen neighborhood left three people dead, including two children.

In a scene police described as "hellish," a woman in her early 30s and a girl in her early teens were found dead in the apartment, along with a wounded boy, age 8 to 12, who was rushed to Regions Hospital, where he died a few hours later, police said Saturday night.

An hour before the shooting, a police officer had been called to the apartment on a welfare check and was assured by the woman who answered the door that she was all right, police said. He then left.

Police believe that the woman who answered the door was among those killed.

The shooting occurred on the 700 block of Jessie Street in St. Paul, just blocks from the scene of a double homicide that occurred on Jan. 21.

"This is a senseless tragedy that's left us all heartbroken — as police officers, as human beings, as members of the community," Police Chief Todd Axtell said late Saturday.

Officers were called to the apartment just after 3 p.m. to assist paramedics with an unknown medical situation. When police arrived, they were met out front by the 911 caller, who said people were injured inside, said Sgt. Mike Ernster, the department's public information officer.

Officers found a "hellish scene" inside the apartment, Axtell wrote in an emotional Facebook post.

"Every homicide is hard, but this is especially a tough one," Ernster said. "It's tough because it involves kids and we had an officer at the home an hour before this call."

Ernster said the officer had been called to the home by a family member who wanted a welfare check done on a female in the residence. "They wanted to make sure she was OK," Ernster said.

He said the officer spoke with the woman and she looked the officer in the eye and said, "I'm OK; tell them I'm OK."

The officer asked her if she wanted to call the family herself, and she declined.

Ernster said that the woman who spoke to the officer is believed to be the deceased woman in her 30s found an hour later in the apartment.

According to dispatch audio, the person who found the victims did not witness the shootings or observe anyone coming or going from the apartment.

Soon after discovery of the bodies, police secured the scene, blocked off the area, and began looking for witnesses and any evidence. Homicide investigators worked to determine what led to the shooting.

The department's Forensics Services Unit will process the scene in hopes of finding physical evidence that will tell the story of what led to the shootings, the department said in a news release.

"Our investigators are working doggedly to find who is responsible for these deaths," Ernster said.

The Ramsey County medical examiner will positively identify the victims and determine an exact cause of death.

The deaths bring the number of 2021 homicides in St. Paul to six. St. Paul experienced 34 homicides in 2020, tying with 1992 for the grim annual record of most in a year.

Both St. Paul and Minneapolis have experienced a sharp uptick in violent crime since George Floyd's death in police custody last May and the unrest that followed.

Staff writers Liz Sawyer and Pamela Miller contributed to this report. Randy Furst • 612-673-4224 Twitter: @randyfurst