For months, authorities say, a young woman calmly walked into a Robbinsdale gun store and legally bought guns big and small, including a Lady Lavender model Charter Arms .38-caliber revolver.

She apparently didn't keep them long. Investigators say she quickly — sometimes immediately — turned the weapons over to Fausi Mohamed, a member of the well-known Somali Outlaws gang, and some were used in a violent crime spree across the Twin Cities this summer.

The allegations are contained in a federal search warrant filed this month for the Burnsville townhouse shared by Mohamed and the woman, described as the mother of his child. The search, conducted by ATF agents in the early morning hours of July 2, uncovered at least six boxes of ammunition, a laser and rifle sight, a permit to carry a gun, an empty holster and a gun practice target.

Mohamed, 21, and the 22-year-old woman have yet to be charged, but Mohamed is facing charges of second-degree assault for pointing a gun at a McDonald's restaurant employee in Uptown.

The federal search warrant states that there is probable cause to believe that between February and June the woman and Mohamed had unlawfully and knowingly made false oral and written statements intended to deceive the gun dealer about the lawfulness of the sale of firearms.

Charges are fairly uncommon against straw buyers, people who buy guns legally on behalf of people who cannot. But gang-related crimes involving guns bought that way are a recurring theme. In November, U.S. Attorney Andy Luger charged members of two rival Minneapolis gangs for receiving illegal guns used in some 15 killings or shootings.

A mentally unstable man who was shot and killed after firing at officers at New Hope City Hall in January received a gun from a straw buyer.

The ATF works closely with gun shops to identify potential straw buyers, training sellers about regulations and having them monitor multiple purchases by a single person. Nationwide, the ATF runs more than 340,000 background checks each year.

The gun-buying scheme involving Mohamed and the woman started Feb. 4 with the purchase of a 9-millimeter semi-automatic pistol, the search warrant said. Like clockwork, she returned to Bill's Gun Shop & Range each month, buying four more guns, including a .45-caliber Glock.

With every gun purchase, the woman passed the required background check and marked on the form that she was the actual buyer of the firearm. The form warns that "you are not the actual buyer if you are acquiring the firearm on behalf of another person."

John Monson, the store's owner, said he recalled seeing the woman at the store and was happy to turn over in-store surveillance video to authorities. He believed she was careful during her purchase because his employees "would have shut her down" if they saw Mohamed give her cash and then take the guns.

"We send the paperwork to the government for checks and they tell us if it's OK," he said. "The bad guys who get the guns don't usually get caught until they do something wrong."

If his employees see suspicious activity, Monson said they log it and discuss the issues at a weekly meeting.

"I'm constantly pushing our guys to look for straw buyers," he said. "But you couldn't look at this woman and say her boyfriend looks like a gang member, so we can't sell her a gun."

Crimes ensue

The crime spree, according to the search warrant, started April 24 when a driver called 911 after another motorist pointed a gun at him about 7:30 a.m. in Hopkins. The State Patrol stopped a vehicle occupied by Mohamed and a 21-year-old man. The vehicle was stolen and troopers found a gun bought by the woman. The gun was loaded with 17 hollow-point rounds.

Less than two months later, Minneapolis police encountered Mohamed and two other people after receiving a report about a possible business robbery.

Two guns bought by the woman and numerous magazines for handguns were found in their car, the search warrant said.

On June 8, Burnsville police responded to a report of a stolen gun from Mohamed's townhouse. Later that month Burnsville police were called to a shooting at a gas station on Southcross Drive. A man had been shot by a gun bought by the straw buyer, the search warrant said. A concerned citizen called police and said Mohamed was the shooter.

By this time, the ATF had received in-store video surveillance from Bill's Gun Shop. It showed the woman, Mohamed and another man buying guns. At no time does the woman appear to handle the firearms, the search warrant said.

She pays for the weapon, but she appears to receive money from a man who looks like Mohamed, the search warrant said. He carries the weapons out of the store, while the woman makes several calls on her cellphone.

Apparently unaware he was under federal investigation, on July 5 Mohamed got into a fight with a McDonald's employee in the restaurant parking lot. At one point, Mohamed told him, "I'll shoot you," the criminal complaint said.

He was arrested a short time later and admitted to the fight but not to having a gun. Witnesses told police Mohamed was heard saying that he was "strapped."

Mohamed and the woman could not be reached for comment.