KUNDUZ: A car bomb killed an intelligence official from Afghanistan's northern Kunduz city on Thursday morning, two days after suicide attackers killed four security guards at a guesthouse in the city used by foreigners, a police spokesman said.

Three children were also wounded by the blast from the bomb planted in the car of Payenda Khan, head of a National Directorate of Security district in Kunduz city, said Sayed Sarwar Husaini, spokesman for the provincial policeman.

Husaini had earlier said Khan was head of the National Directorate of Security in Kunduz province, but later said he was given incorrect information by officials at the bomb site.

The killing comes after three suicide bombers on Tuesday attacked a guesthouse in Kunduz, killing four Afghan security guards employed by a German company.

The once peaceful north of the country has seen a series of high profile attacks and assassinations in recent years, as insurgents seek to demonstrate their reach beyond their traditional southern heartland around Kandahar city.

Violence is at its worst in Afghanistan since US-backed Afghan forces toppled the Taliban government in late 2001, with high levels of foreign troop deaths, and record civilian casualties.