International flights landed at Nairobi airport Thursday morning, the first since a fire a day earlier gutted the arrivals terminal causing widespread chaos and delays, airport officials said.

The fire forced the cancellation or diversion of scores of flights at east Africa's biggest transport hub.

A massive fire engulfed the arrivals hall at Kenya's main international airport early Wednesday, forcing East Africa's largest airport to close and the rerouting of all inbound flights.

Dark black smoke that billowed skyward was visible across much of Nairobi as emergency teams battled the blaze. Stranded passengers stood on sidewalks outside the airport with their luggage in hand.

Two more people died of their wounds Saturday following a grenade attack near a Nairobi mosque, bringing the toll to five and heightening security concerns three months before Kenya goes to the polls.

"Two more people have died in hospital, the death toll is now five," Nairobi Police Chief Moses Nyakwama told Agence France Presse, updating an earlier toll of three.

One person has died hours after a bomb blast in the Kenyan capital that wounded eight others, the latest in a string of attacks, police said Thursday.

The attack, a "roadside bomb which had been placed in a hole in the ground,” according to Nairobi police chief Moses Nyakwama, was detonated during rush hour on Wednesday evening as people returned home from work.

Inter-ethnic clashes broke out on Monday in a Nairobi district over a bus bomb blamed on sympathizers of Somalia's Al-Qaida-linked Shebab insurgents, leaving several people wounded.

An AFP reporter at the scene said police used tear gas and fired into the air to contain the violence, which broke out at Eastleigh, a predominantly Somali district of Nairobi where a bomb that went off Sunday on a bus killed seven and wounded many more.

Gunmen killed 10 people and wounded dozens when they opened fire and hurled grenades into two churches in the eastern Kenyan town of Garissa on Sunday, the latest in a string of attacks, police said.

Gunmen burst into the churches in apparently coordinated attacks targeting worshippers as they held Sunday prayer services in Garissa, some 140 kilometers (85 miles) from the border with war-torn Somalia. The attackers later escaped.

A grenade set off by a worshipper in a Nairobi church killed one person on Sunday and injured at least 10 others, police in the Kenyan capital said.

"We have one fatality, and there are more than 10 others who have been injured," area deputy police Chief Joseph Gichangi said.

Kenyan police said Monday they have arrested four people in connection with grenade attacks that killed six people in Nairobi, which Kenya blames on supporters of Somali Shebab insurgents.

"On the Al-Shebab threats and attacks at the Machakos bus terminus, four highly suspected criminals were arrested and are undergoing intensive interrogation," Nairobi Provincial Police chief Antony Kibuchi said.

Kenya faced a new terror threat on Sunday after a grenade attack blamed on Somali Islamist militia killed six people and injured 63 in a bus terminal in the capital Nairobi.

Four grenades were thrown Saturday night only yards apart from a car driving past the busy terminal, Internal Security Minister George Saitoti said Sunday.

Britain said Saturday it believed there was a heightened threat of "terrorist attacks" in the Kenyan capital Nairobi and that attacks "may be in the final stages of planning".

"The Kenyan authorities have alerted the public to a heightened threat from terrorist attacks in Nairobi. We believe that terrorists may be in the final stages of planning attacks," a Foreign Office statement said.