A Taliban suicide car bomber attacked a convoy from the European Union police training mission Sunday near the Afghan capital's international airport, killing at least three people, including a Briton, authorities said.

The attack in Kabul comes amid a stepped-up Taliban campaign that saw its militants attack a guesthouse days earlier in Kabul, killing 14 people, including nine foreigners.

The assaults show the challenges facing Afghan security forces, which have been in charge of their country's war since NATO and US troops ended their combat mission at the end of last year.

The car bomb exploded early Sunday morning near the office of the Afghan Civil Aviation Authority, a few hundred meters (yards) from the airport's main terminal, said Najib Danish, a deputy Interior Ministry spokesman.

The blast damaged one foreign vehicle and two civilian vehicles, he said.

Sari Haukka-Konu, a spokeswoman for the EU's police mission, said one non-mission member traveling in a EUPOL vehicle had been killed. The British Embassy in Kabul identified the dead Briton as a security contractor, without elaborating.

Britain's Foreign Secretary Phil Hammond called the attack cowardly.