Somalia's al-Qaida-linked Shebab claimed responsibility on Saturday for an attack on a bus and police vehicle on Kenya's restive southeastern coast that killed at least seven people.

A Kenyan court on Thursday gave prosecutors an additional month to conclude their investigation into a regional governor accused of links to a spate of massacres.

Governor Issa Timamy of the coastal Lamu county was arrested in connection with last month's killings in the town of Mpeketoni and nearby villages, which were claimed by Somalia's al-Qaida-linked Shebab militia but blamed by the government on local political networks.

A former top U.N. envoy said Wednesday that Somalia's al-Qaida-linked Shebab rebels will be defeated if foreign governments stay the course in backing the fragile government in Mogadishu.

Speaking at Land Forces East Africa, a two-day regional defense conference and military technology exhibition, the former envoy to Somalia played down a recent upsurge in Shebab attacks inside the country and across the border in Kenya.

Kenya's opposition leader Raila Odinga has accused the government of failing to safeguard national security in the face of a wave of Islamist attacks and has warned of mounting internal ethnic tensions.

He said the east African nation was now in a state of permanent anxiety because of attacks by Somalia's Al-Qaida-linked Shebab insurgents, and that Kenya should pull its troops out of Somalia.

Amnesty International on Tuesday condemned what it said was the Kenyan government's continued failure to properly investigate and deliver justice and compensation to victims of the 2007-2008 post-election violence.

"Six years after post-election violence rocked Kenya, the victims are still awaiting justice. It is vital that their voices are heard and urgent action is taken," said Amnesty secretary general Salil Shetty.

Unidentified gunmen raided a village near Kenya's restive coastal town of Lamu early Friday, Kenyan officials said, the latest in a string of attacks in the region.

Officials said more than 10 raiders struck at Pandanguo village, about 40 kilometers (25 miles) from Mpeketoni -- where close to 50 people were massacred in an attack last month -- stole guns from police reservists and torched houses and other buildings. 

Lawyers representing Kenyan President Uhuru Kenyatta have renewed calls for the International Criminal Court to drop charges of crimes against humanity against him.

"We have reached a stage where there is no evidence" to support the charges, Kenyatta's lawyer Steven Kay told judges in The Hague on Wednesday.

Gunmen in Kenya launched two separate attacks, killing one person by hurling a grenade into a restaurant in the restive northeast, and torching conservation offices on the coast near Lamu, police said Tuesday.

At least one person was killed and several injured late Monday in the grenade blast in a restaurant in Kenya's northeastern town of Wajir, before spraying the building with bullets and escaping, police said.

Thousands of Kenyans rallied Monday for an anti-government demonstration in the capital's central park amid heavy police presence, with political and ethnic tensions high following weekend attacks in which over 21 were killed.

Opposition leader and former prime minister Raila Odinga has organized the rally to address what he says are major government failures, including worsening crime and insecurity, rising living costs, impunity, corruption and allegations of ethnic favoritism in government appointments.

A Russian tourist was shot and killed while touring a historical site in Kenya's port city of Mombasa on Sunday, police said.

Kenya's deputy police chief said the murder was being treated as "normal thuggery" and not a terrorist incident, explaining the woman was shot after resisting an attempt to steal her camera.