Four people were charged Tuesday in connection with a brutal weekend robbery that ended with two men being severely stabbed in a Fridley parking lot.

Kevin Moore, 25, of Spring Lake Park, and Marcus Fultz, 20, of Woodbury, each face six charges in the Saturday night attack, including attempted murder, first-degree assault and attempted aggravated robbery. The two are accused of repeatedly stabbing Anthony McCollum and Yani Singh.

McCollum and Singh, both 21, were at Two Stooges Bar & Grill about 2 a.m. Saturday when two women asked them for a ride to a nearby apartment complex, where they were attacked. The women, Leanne Todd and Tiffani Ivy, both 22, each face four charges, including aiding and abetting first-degree assault.

McCollum, of Hilltop, and Singh, of Columbia Heights, remained in critical condition Tuesday at Hennepin County Medical Center in Minneapolis.

"This is a very serious crime, and we are pursuing the investigation vigorously," Anoka County Attorney Tony Palumbo said in a prepared statement.

Ivy admitted to police that the four defendants conspired together to rob the two victims, then changed her story a couple of times, according to the criminal complaint.

McCollum and Singh had agreed to give the women a ride to a parking lot near Todd's apartment off University Avenue NE. and NE. Mississippi Street, the complaint said.

Ivy later admitted that when the bar closed, she and Todd left the bar with the men and a third man, then stopped at a gas station before going to one of the men's apartment for two hours. The two victims then drove the women to Todd's apartment while the third male stayed behind.

At 4:20 a.m., McCollum called police from near 77th Avenue NE. and Main Street, saying he and his friend had just been attacked by two strangers and had managed to flee. McCollum had been stabbed in his chest, left arm and side. Singh had a chest wound that punctured his lung.

Initially, Ivy told police that after they pulled into a parking lot, the women got scared and ran away when two males approached the car. But later she changed her story and admitted that she and Todd had been dropped off at the bar and had conspired with Moore and Fultz.

Ivy said she had no idea Moore and Fultz were going to stab McCollum and Singh, according to the complaint. She said Moore approached the driver's side door and yelled, "This is a robbery!" while Fultz approached the back-seat passenger door.

Todd denied meeting the men or receiving a ride from them.

The stabbings occurred less than a week after Moore had completed a prison sentence for first-degree aggravated robbery conviction in Anoka County in 2011. He served time in that case until June 30, then came off supervised release on Aug. 17.

Moore's criminal history in Minnesota also includes several convictions for damage to property and for underage drinking and other alcohol-related offenses.

Fultz appears to have no criminal record in Minnesota.

Todd has a minor drug possession offense on her record, while Ivy appears to have no record.

Anoka County District Court Nancy Logering set bail for Moore at $1 million without conditions and Fultz at $750,000 without conditions. Bail for Todd and Ivy is set at $250,000 each, without conditions.

All four suspects are set to appear in court in September.

karen.zamora@startribune.com • 612-673-4647 paul.walsh@startribune.com • 612-673-4482