Washington  - It was an audacious crime that terrified people in the US capital for weeks. John Allen Muhammad and his 17-year-old accomplice Lee Boyd Malvo armed themselves with a sniper rifle and went about executing random residents across the city.

Muhammad, known as the DC sniper, will be executed Tuesday evening for shooting at least 16 people - killing 10 - in October 2002 in Washington and surrounding cities in Virginia and Maryland.

The biggest death toll came at the start - a two-day span between October 2 and 3 when Muhammad and Malvo shot and killed six people. They had armed themselves with a sniper rifle and drilled a hole in the back of their car's trunk. There was no pattern to the attacks.

Sarah Ramos, 34, was killed October 3 while sitting on a bench outside a shopping centre in Silver Spring, Maryland. Dean Meyers, 53, was killed October 9 while refuelling at a petrol station in Manassas, Virginia. Others were shot outside liquor stores or simply waiting to cross the street.

Muhammad, who was 41 at the time of the shootings, was sentenced in 2004. He will be put to death by lethal injection in southern Virginia, in front of a small group of victims' family members.

Malvo, who saw Muhammad as something of a father figure, was only 17 at the time of the shooting. He was sentenced to life in prison without the possibility of parole.

Muhammad's lawyers attempted to get him a last-minute stay of execution. The Supreme Court rejected his appeal on Monday. Virginia Governor Timothy Kaine is the only person who still has the power to spare his life.

Before reaching the capital, authorities believe the snipers took the lives of at least six other people during a cross-country killing spree that began in their home state of Washington on the West Coast.

The shootings threatened to bring Washington to a standstill. Many were afraid to leave their homes and nobody felt completely safe. Muhammad and Malvo were eventually caught on October 24 as they were sleeping in their car at a highway stop in Maryland. (dpa)