Mombasa - Kenyan police shot dead three suspected supporters of the Somali militant group al-Shabaab on Wednesday during a raid in Kenya's turbulent coastal region in which a police officer also died.
Police arrested a number of suspects and confiscated grenades, AK-47 assault rifles and ammunition at a house in the Likoni area, Coast province police chief Aggrey Adoli said.
Kenya has suffered a series of grenade and gun attacks since it sent troops into Somalia a year ago in pursuit of the insurgents it blames for kidnapping security personnel and Western tourists from its territory.
A local group campaigning for secession of the Coast region has added to tensions ahead of presidential elections due in March, the first a disputed 2007 vote that sparked nationwide bloodletting in which more than 1,200 people were killed.
Adoli said the suspected al-Shabaab supporters hurled two grenades and opened fire when an elite Nairobi police unit burst into their building, seriously wounding four officers. One later died of his wounds in hospital.
"The operation is still on. We have arrested several suspects, but it's still too early to say how many until we are through," Adoli told Reuters by phone.
Mwagomba Juma, a youth leader who lives in the area, said heavy gunfire, punctuated by at least two blasts, broke out around 2 a.m. and lasted until the early hours of the morning.
Dozens of police in bullet-proof vests and armed with automatic rifles combed the neighbourhood as nervous residents peered through the windows of their houses, witnesses said.
The instability has spooked foreign tourists. Visitors were down by a fifth in the first eight months of this year, a heavy blow to the tourism sector which is a key driver of East Africa's biggest economy.