The search continued Thursday for Michigan woman Tonya Jackson, and the case of the 42-year-old Ypsilanti mom who disappeared Saturday is raising “more questions than answers,” according to local law enforcement.

Jackson was last seen at Knights Inn in Romulus with a friend, a spokesman for the Washtenaw County Sheriff’s Office told the Ann Arbor News. The spokesman, Derrick Jackson, said so far there’s no evidence indicating Tonya  was the victim of foul play.

“She met up with a friend at Knights Inn at about 7 p.m. on Saturday, May 3,” Derrick Jackson said. “We’ve spoken to the friend and right now nothing says that [foul play is involved], but there are more questions than answers at this point.”

Tonya Jackson’s sister, Nikeyta Evans, said it was unusual for her to be at a hotel without her family. Tonya Jackson is married with four children.

“It’s suspicious,” Evans told Detroit television station WDIV. “We have actually been out looking for her too. We have been riding around, searching different hotels, parking lots, to see maybe if she got a room."

Evans told the Ann Arbor News that her sister told her she was meeting a friend, but then the friend later told Evans that Tonya Jackson went to have drinks with a co-worker at the Detroit-area hotel.

“The female friend called me and said Tonya went out with a male co-worker for drinks at Knights Inn, but said she didn’t have a good feeling and that she felt like my sister wasn’t OK,” Evans said. ““It’s not likely that my sister would just up and leave like that, though.”

Evans said her sister and her brother-in-law “had little problems, like every marriage does, but nothing that would make her run off. I really don’t know what to think.”

“She would’ve called someone if things were all right, if things were OK,” she said. “She’s not answering for her kids, for her dad, for family and she hasn’t called off at work, which is also totally unlike her.”

Evans said every call she places to her sister goes to voicemail.

“Wherever she is or whoever knows where she is has been charging her cell phone. I hope police can track it down that way or see if her credit cards or bank cards have been used,” Evans said.

Tonya Jackson is described as 5 feet 7 inches tall, weighing 180 pounds, with brown eyes. She was driving a silver 2007 Saab 9-7x with Michigan license plate CCL 7888. Anyone with information on her whereabouts is urged to call the Washtenaw County Sheriff’s Office confidential tip line at 734-973-7711.