Nairobi, Feb 7 (IANS): Unidentified gunmen killed four people, including a lawmaker, in Kenya's capital Nairobi early Saturday.

Nicholas Kamwende, head of the Nairobi Criminal Investigation Department, said legislator George Muchai, his two bodyguards and a driver were sprayed with bullets at about 3 a.m. when their vehicle slowed down in the city centre. He said all the four occupants died in their seats in a Toyota Fortuner vehicle.

"The attackers seem to have trailed the victims from Westlands to the scene where the shooting happened. We are yet to know the motive," Xinhua news agency quoted Kamwende as telling journalists.

Eyewitnesses at the scene said the car was sprayed with bullets by men in a private car, the number plates of which were concealed. Witnesses said the gunmen fired about 10 bullets before Muchai went for two pistols that the bodyguards had in a briefcase that was in the car. Muchai's licensed gun was found in his holster.

Muchai, who joined parliament in 2013, was a representative of the Central Organisation of Trade Unions, an umbrella workers body.

Kenya has grappled with a security breakdown in recent years as cases of armed robberies, kidnappings and murders in cities and villages reached a crisis level. Crime has surged to record levels in Nairobi and its environs as armed gangsters raid homes and business premises.