Three American men and a South Korean were among seven people who died on Friday when a fire razed a hotel in a red-light district near a former US naval base in the Philippines, authorities said.
The fire occurred before dawn at the budget Dryden hotel in Olongapo, a port city about three hours' drive north of Manila, police said.
Three of the victims were American men, another was a South Korean man and two were Filipina women, police investigator Tyrone Tecson told AFP.
Police said a seventh person, believed to be a Philippine citizen but not yet identified, was also killed.
City civil defence chief Angelito Layug said authorities were investigating whether the three Americans may have belonged to the "fairly large" population of retired American servicemen who live in and around Olongapo.
Many settled there after the US military pulled out of the nearby Subic Naval Base in 1991, Layug said.
The Dryden hotel advertises itself on the Internet as catering for people who want to visit scantily clad dancers and "guest relation officers" in neighbouring bars.
"Nestled right in the middle on the famous nightlife district... a clean budget priced hotel that is internally connected to 5 of the hottest gogo bars in town, the ideal hotel for 'singles'," the hotel's website says.
Olongapo police said hotel building was located in a compound that included several bars.
"It's one of the most famous establishments in the area," Olongapo mayor James Gordon told AFP.
Gordon and police said the cause of the blaze was not yet known, while the US embassy in Manila had no immediate comment.
"We are still gathering information," US embassy spokeswoman Tina Malone told AFP.