* Suspected drug hitmen kill six men on U.S. border

* Hitmen kill police chief near wealthy Monterrey

* Attacks latest violence in escalating drug war (Updates with killing of police chief in northern Mexico)

By Julian Cardona

CIUDAD JUAREZ, Mexico, Nov 4 (Reuters) - Gunmen with automatic weapons burst into a Mexican strip club on the U.S. border, opened fire on patrons and killed six people including an American soldier, the army said on Wednesday.

The hooded gunmen stormed into the bar in Ciudad Juarez as strippers were dancing for customers, sought out the six men and shot them each several times. A 26-year-old off-duty U.S. soldier who had crossed over from El Paso, Texas, was among the dead, army spokesman Enrique Torres said.

"It appears drugs were being sold at the place," Torres said of the strip joint. "The hitmen went directly for their victims, no one else."

The suspected drug hitmen escaped the bar easily, while panicking customers fled in their cars as pools of blood gathered around spent bullet cases on the bar floor.

In a separate assault near the wealthy northern city of Monterrey, around 30 suspected drug hitmen killed a municipal police chief just five days after he took up his post, and left a threatening warning for the local mayor, police said.