Concerns have been raised about two Minnesota brothers with ties to the Middle East after they were allegedly found with bomb-making materials, guns and ammunition in their car.

Abdullah Alrifahe, 27, and Majid Alrifahe, 26, were arrested on May 11 outside a senior housing project in north Minneapolis.

The elder brother has been charged with a single weapons felony and is being held in the Hennepin County Jail on $200,000 bail.

Brothers Abdullah Alrifahe, 27, (left) and Majid Alrifahe, 26, (right) were arrested on May 11 outside a housing project in Minneapolis after police found bomb-making materials in their car

Majid has already been released and is facing misdemeanor charges, including disorderly conduct. The offense in Minnesota carries a maximum punishment of 90 days in jail or a $1000 fine.

Both Homeland Security and the FBI are involved in the investigation, WCCO-TV reports.

A man had confronted them outside the senior housing project about littering from their car when he claims they jumped out of the vehicle and aggressively moved towards him.

They were arrested outside a senior housing project in north Minneapolis after a man approached them about littering from their car

Police were called and allegedly found a loaded AK-47, a rifle, handgun, a grenade, ammunition, bomb-making materials and a drone inside the car.

The man who initially confronted them and called police is outraged the two brothers aren't facing more serious charges.

'For what they found in their car, that is way too light,' he told WCCO-TV.

The Minneapolis Police Department say they are still investigating, while the FBI had no comment about the case.