GRAND FORKS, N.D. — A North Dakota couple died while vacationing in San Diego when a 75-foot-tall pine tree crashed onto their rental house as they slept, relatives and police said.

Troy and Jessica Nelson ran a promotional products and apparel company, Trojan Promotions, in Grand Forks.

They were spending the weekend at the house after attending a trade show during the week, according to the man's sister Tammy Reynolds. They were sleeping upstairs when the tree toppled in gusty winds around 6 a.m. Monday.

Reynolds said her sister-in-law's brother, Ryan Langerud, was on the first floor of the house and survived.

"It's such a freaky accident," Reynolds told The San Diego Union-Tribune. "I guess we're all so numb from it, and for both of them to go."

Reynolds said Langerud told her he found himself in the basement with items on top of him and initially was confused as to what had happened. She said Langerud told her it sounded like an airplane had crashed into the house.

Trojan Promotions senior production manager Krisi Lund said Tuesday the future of the company is up in the air as its employees grieve the deaths of the Nelsons.

"We carry on day by day. The future of the company hasn't been decided. We're committed to our clients. We are going to take care of our clients the best we can the way Troy and Jessica would want us to," Lund told The Associated Press. "They were generous beyond belief in every aspect of their lives."

San Diego Police Lt. Christian Sharp said the fallen tree caused a gas leak in the house and clipped some power lines.