Authorities in northern Mexico have confirmed four people died of swine flu in the border state of Chihuahua.

Chihuahua state Gov. Cesar Duarte says six other people have been infected with the H1N1 virus.

Duarte says one woman died of the flu in the capital city of Chihuahua after returning from a trip to Texas. Two traffic police officers in Ciudad Juarez and a woman in the city also have died.

Duarte says the swine flu flare-up is associated with an outbreak in Texas and New Mexico.

Duarte made his comments during a vaccination event Sunday.

Mexico's Health Secretary Jose de Cordoba recently said there has been an increase in seasonal flu cases but not swine flu.