Two more victims of a horrific Alberta highway crash that killed seven people were identified Sunday.

CTV Edmonton reports that Courtney Penney, 28, was killed in the fiery collision and her husband Mark Penney, 34, is in an Edmonton Hospital in serious condition. Courtney Penney, who is originally from Nova Scotia, was six months pregnant.

The couple was travelling in the same pickup truck with a Fort McMurray pastor and his family when their vehicle struck another pickup on Highway 63 about 1 p.m. local time Friday. Both vehicles burst into flames.

Shannon Wheaton, his wife Trena, and their youngest son Benjamin, 2, were killed in the crash. The family's oldest son, Timothy, 3, survived with only minor injuries.

The two couples knew each other from the same church they attended in Fort McMurray.

Three people in the other pickup truck, including an 11-year-old girl, were also killed and have yet to be identified by police.

Members of Wheaton's church, where he served as a pastor, were grieving the loss of the family members Sunday in the first service since the fatal crash.

Rev. Edwin Rideout, of the Family Christian Centre, said Wheaton joined his staff in 2010, but they previously worked together for five years with a congregation in Springdale, NL.

He called Wheaton one of the most gentle and generous people he knew. The church will be providing grief counselling until Wednesday, he said.

"We're just a community in mourning right now," an emotional Don Scott, MLA for Fort McMurray-Conklin, told CTV Edmonton on Sunday.

Police haven't released the identity of the other crash victims. Just two people, including Timothy, survived the crash.

The collision occurred on a two-lane stretch of Highway 63 near Wandering River.

Police have ruled out alcohol and speed as factors in the crash, CTV Edmonton's Bill Fortier reported.

"They do believe weather conditions played a role . . . it had just snowed so the roads were somewhat slick," Fortier said.

There have been several deadly crashes on the busy highway that links Fort McMurray and Edmonton.

Friday's tragedy has led to renewed calls for the province to twin the remaining two-lane sections of the highway.

Fort McMurray is in the middle of the province's oil sands development and its population has surged by about 100,000, increasing traffic on the highway, Fortier said.

The province has promised a four-lane highway but hasn't offered a completion date, he said.