A hand grenade was hurled at a vehicle carrying two British tourists in Kenya as the country marked 50 years of independence from Britain on Thursday (December 12). Police said the device failed to explode.

Likoni police chief Robert Mureithi said there was no obvious link between the national celebrations and the incident in the coastal city. Mombasa is dependent on tourism and has been plagued by attacks blamed on Islamist militants and their sympathisers.

"A suspect tried to throw something which resembled a grenade into a motor vehicle. Fortunately, it hit the passenger's door and landed by the side. The two passengers who were in the tour van were unhurt," said Mureithi.

The incident threatened to deal another blow to the tourism industry, a mainstay of East Africa's biggest economy. In September, Islamist militants killed dozens of people in an assault on a Nairobi shopping mall.

Tourist arrivals in the first five months of 2013 were down 15 percent on last year as visitors stayed away, worried by attacks blamed on Somalia's al Shabaab rebel group and by the risk of trouble during elections in March, which passed off peacefully.

Kenya is marking half a century of independence from British rule at a time when anti-colonial rhetoric is on the rise as the country's president and his deputy face trial for crimes against humanity at the International Criminal Court in The Hague.

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