A 23-year-old man has been charged with four counts of first-degree murder after the bodies of three women and one man were found in a home in Markham, Ont., York Regional Police say.

Menhaz Zaman, who is from Markham, is in custody and appeared in a Newmarket courtroom on Monday. He was remanded into custody and is expected to reappear in court via video link on Aug. 2.

Zaman, wearing glasses and a black T-shirt, was brought handcuffed into the prisoner's box. He gave his name in a soft voice.

Police received a call shortly before 3 p.m. ET Sunday about several people possibly injured inside a home on Castlemore Avenue in Markham, a city about 30 kilometres northeast of downtown Toronto.

Const. Andy Pattenden, spokesperson for York Regional Police, declined to say where the 911 call originated from or who called police.

Officers who arrived at the home encountered a man at the front door. Police took him into custody, then shortly after the arrest, they searched the home and found the four bodies.

A York Regional Police vehicle is parked outside a home in Markham, Ont., north of Toronto, where four people were found dead. A man, 23, has been charged with four counts of first degree murder. (CBC)

Pattenden said police will release the names of the victims once post-mortems have been completed.

"We are not looking for any further suspects in this case at this time," Pattenden told reporters near the scene on Monday. "We do believe that the man we have in custody that has now been charged is responsible for these murders."

Suspect lived in home with his family, neighbour says

Police say they will release more details about the relationship between the suspect and victims once the bodies have been identified.

Ammara Riaz, a neighbour who had previously lived as a tenant at the residence where the bodies were found, told CBC News that Zaman lived in the home with his grandmother, mother, sister and father.

The cause of death of the four people has not been released. Pattenden declined to comment on the nature of their injuries.

Pattenden also wouldn't comment on whether the suspect has a criminal record, and could not say if next of kin have been notified about the deaths.

Const. Andy Pattenden said investigators would like anyone who saw or heard anything in the area to come forward. (Richard Agecoutay/CBC)

On Sunday night, a crowd gathered near the home after police taped it off.

"We want to reassure the community that York Regional Police has been here throughout the night, been here ever since we got the report, and I can guarantee that this community is very concerned," he said.

"There were 200-plus people out last night when I was here at the scene, and we want to reassure them we do have this person in custody and he's now facing charges."

Investigators are calling on anyone who may have seen or heard anything in the area to come forward and call police.

A coroner and homicide detectives were at the scene Monday.