The live-in gal pal of mass killer Stephen Paddock returned to the United States late Tuesday, officials said.

Marilou Danley, 62, touched down at Los Angeles International Airport, where she was greeted by federal agents, authorities said.

Investigators are eager to interview Danley, who was overseas when her boyfriend carried out the worst mass shooting in US history on Sunday night, killing 59 people at a country music festival in Las Vegas.

The Clark County sheriff has said Danley is considered a “person of interest.”

A Philippines immigration spokeswoman said Wednesday that Danley had arrived in the Philippines on Sept. 25 on a flight from Hong Kong.

With Post wires