An elderly Kenyan man was clawed by a lion that was wandering along a busy road during morning rush hour in the capital Nairobi on Friday, wildlife officials said.

It is the third time in a month that lions have caused panic as they roamed outside of Nairobi National Park, a 117 square kilometre (29,000 acre) reserve almost surrounded by a fast-growing city of over three million people.

The 63-year-old man was injured when the lion became agitated and swiped at him, said Kenya Wildlife Service (KWS) spokesman Paul Udoto.

"People were there, hooting their horns, taking selfies and all that and the lion got agitated," Udoto said, adding that the man was taken to hospital and was in stable condition.

Soon afterwards, the lion returned to the park, followed by rangers who encouraged it to move deeper into the reserve.

"The lion is safely back but our teams are still on the ground in case there are any others around that have not been spotted," Udoto said.

In a video shared on social media, commuters honked their horns continuously at the large, dark-maned male lion as it trotted along Mombasa Road, a traffic-clogged four-lane highway that is one of the capital's main arteries.

Bystanders peered out from behind fences and gates.

The park is not entirely fenced to enable traditional migration by animals in search of grazing.

The big cats are under growing pressure as one of Africa's fastest growing cities expands onto ancient migration routes and hunting grounds.

Conservationists say lions predate people in the area and are not "escaping" the park nor "straying" into human settlements, rather people have moved into the lions' home ranges.

In mid-February, two lions spent a day wandering through Kibera, a densely-packed city slum, before returning to the park, and days later more lions were spotted in town.

While lions on the loose are increasingly common in Nairobi, it is unusual for anyone to be injured during their outings.

Troops clear wild animals from Sri Lanka's white-elephant airport
Colombo (AFP) March 18, 2016 - Sri Lanka has deployed troops and firecrackers to clear deer and wild buffalo from a sprawling airport, officials said Friday, drawing attention to a largely redundant vanity project built by a former president.

Mattala airport, which services just one flight a day, was built in the home district of former strongman leader Mahinda Rajapakse, 250 kilometres (155 miles) by road from the capital Colombo, at a cost of $210 million.

This week some 350 troops, police and volunteers spent a day driving out about 150 deer and 50 buffaloes that had apparently become trapped when an electric fence was set up to prevent wild elephants straying into the facility.

An airport official involved in the operation said animals regularly got in the way of flights at the site, which lies in the middle of two wildlife sanctuaries and on an avian migratory path.

"We used fire crackers to scare the animals and push them out of the perimeter, but it was not very successful," he told AFP on condition of anonymity, adding that a bigger operation was planned shortly.

There have been no accidents involving deer or cattle at Mattala, but the first flight to land there was struck by a bird, shattering its windshield.

Another aircraft had to be grounded after one of its engines was destroyed when a peacock flew into it.

The airport employs 550 workers and is only used as an alternative when aircraft cannot fly into Colombo's international airport.

Faced with a huge white elephant, the authorities last year turned some of the air cargo terminals at the Mattala airport into rice storage to accommodate the bumper harvest in the region.

Former president Rajapakse spent lavishly on infrastructure and was criticised for ignoring feasibility studies and environmental warnings.

His projects included a deep-sea port, six-lane highways, an international conference centre, a cricket stadium and a dry-zone botanical garden.