Drugs and alcohol may be to blame for the sudden and suspicious deaths of two Metro Vancouver teenage girls, Mounties say.

The 16- and 17-year-old victims died just hours apart on Tuesday morning. The girls were friends and witnesses report seeing them together on Monday night, according to Burnaby RCMP.

The younger victim, a Vancouver resident, was found collapsed in the 4000-block of Rumble Street in Burnaby at about 12:40 a.m. Tuesday morning. She went into medical distress and did not survive.

Only hours later, the girl's 17-year-old friend also went into medical distress in her Richmond home and died.

Friends have identified the girls as Kayla LaLonde and Martha Jackson Hernandez.

Tributes have been pouring in to a Facebook memorial page set up for both teens.

Lavina Baptiste, a friend of both girls, described the younger victim as a popular student who was always smiling and friendly.

"There was something about her that made you always want to be around her," she said.

A relative of the 16-year-old told CTV News the family is grieving and is trying to come to terms with the tragedy.

Burnaby RCMP say they believe drugs or alcohol may have played a part in the deaths but are awaiting toxicology reports to determine what killed the young friends.

Test results are expected in two weeks.