Kampala, Apr 4 (IANS): Four armed men kidnapped an American tourist in Uganda and have demanded $500,000 as ransom, the country's police force has confirmed.

The American citizen, a woman, and a Ugandan driver were kidnapped at gunpoint at Queen Elizabeth National Park while on a game drive on Tuesday evening, CNN reported on Wednesday.

"The kidnappers, using the victim's phone have demanded $500,000," the police said, adding: "We strongly believe this ransom is the reason behind the kidnap."

An "elite squad" was dispatched from the Tourism Police to the park to actively pursue the gunmen and have closed all exit areas on the border between Uganda and the Democratic Republic of Congo.

"We strongly believe the perpetrators and victims could still be trapped within our search area," the police statement added.

Uganda recorded a spate of kidnapping incidents last year, which prompted street protests amid claims the government was not doing enough to address the security issues.

Rights groups who led the protests to the country's parliament in Kampala city, said more than 20 people, mostly women, and children, were abducted for ransom last year and called on the police to make these cases a priority.