NAIROBI, Kenya (AP) _ Gunmen ambushed a group of American visitors touring a Kenyan game park, killing a Connecticut woman, wounding a man and robbing the group of money and jewelry, a source said.

The attack was the fifth on tourists in Kenyan game parks in less than a year.

The group of 19 Americans was attacked Thursday as they drove in three vans along a 40-mile road between Amboseli and Tsavo national parks in southern Kenya.

''They just jumped out in the road and fired on us,'' Allen E. Sullivan, 66, was quoted as saying in a telephone interview with Connecticut's Hartford Courant newspaper.

Sullivan, a retired high school teacher from Trumbull, Conn., was shot in the chest but the newspaper quoted him as saying he was not badly hurt. He spoke from his hotel in Nairobi.

A woman was shot through the head and killed instantly. In Washington, State Department spokeswoman Frances Jones identified her as Marie Esther Ferraro of New Haven, Conn. Her age was not available.

Sullivan was quoted as saying that two men, one dressed in camouflage clothing, jumped out of the bush about midday and began firing at their convoy of three vans. The gunmen stole money and jewelry from them, he said. Sources said the gunmen used Soviet-made AK-47 assault rifles.

They were on a trip organized by the Connecticut Audubon Society and had 18 people from Connecticut and one from Georgia, society spokeswoman Lauren Brown said in Fairfield, Conn.

Kenyan Police Commissioner Philip Kilonzo and Richard Leakey, director of wildlife, went to the scene to investigate.

It was the fifth attack in 11 months on tourists in Kenyan game parks.

They began in September when a Dutch tourist was shot in the chest in Meru National Park.

Also in September, the remains of a British woman were found in sprawling Masai Mara Game Reserve in southwestern Kenya. An inquest begins Aug. 7 into her death, which her father says was murder. Police say she could have fallen prey to wild animals.

In the first week of July, poachers shot two French tourists to death in Meru National Park, east of Mount Kenya. Leakey had called it an isolated incident. He said he did not think the poachers were ''looking for tourists to shoot.''

In April, three West German tourists were wounded by gunmen who ambushed their vehicles in about the same spot between Tsavo and Amboseli.

Two Americans remain hospitalized after being beaten up last week while on a horseback riding safari in Masai Mara. The U.S. Embassy refused to release details about them.

Maintaining security in Kenya's parks is vital to this East African nation, which has hosted nearly 3 million tourists since 1984. Tourism last year brought in nearly $350 million and became Kenya's top foreign exchange earner after coffee.

After the French couple was killed, the government said it increased security to ensure national parks and game reserves are ''peaceful and comfortable havens'' and make sure the wildlife survive.

Kenya has suffered increasingly from well-armed poachers who stalk and kill elephants for their valuable ivory tusks, primarily in Tsavo.

Since Leakey became wildlife director in March, Kenya has stepped up anti- poaching efforts. Since January, game rangers have killed more than 20 poachers.