Workers drawn to the North Dakota oil fields by the promise of work are getting layoff notices – and thousands more pink slips could be on the way.

CNN Money reports the number of rigs drilling new oil wells in the state dropped to 161 this week, down from 187 this time last year. That's the lowest level in five years.

In addition, the Jamestown Sun says the number is down by more than 20 from just a month ago. The story said there are 750 drilled wells awaiting completion in the Bakken, an all-time record number.

"My prediction is we're down to 50 rigs by June," Jim Arthaud, CEO of MBI Energy Services, told CNN.

Oil companies are slow to bring drilled wells into production as prices for Bakken crude have fallen to around $30 a barrel. That could take a toll on the region, with less work for companies that provide ancillary services.

"I'd say we'll lose 20,000 jobs by June," Arthaud predicted.

KFYR in Bismarck reported the terminations have surprised some of those who have been laid off.

"We heard the rumor first, and they told us everything is going to be okay," said former oilfield chief Stephanie Makente. "Then we come back on the fifth and they said it's over. They closed."

Right now, the Williston unemployment rate remains at a low 0.9 percent, and job service director Cindy Sanford says that while this time may seem tumultuous, many oil companies are either still looking to fill positions.

"There's still jobs," Sanford said.