(CNN) The mother of two missing Idaho children has until Thursday to physically produce them to authorities, according to a court order served by police on Saturday.

Lori Vallow, the children's mother, and her husband, Chad Daybell, were served with a search warrant after authorities found the couple in Hawaii, the Kaua'i Police Department said in a news release on Sunday.

Joshua "JJ" Vallow, 7, and Tylee Ryan, 17, who have not been seen or heard from since September, were not with the couple, and there is no evidence that they were ever in Hawaii, authorities said.

Lori Vallow and Daybell fled their home in Rexburg, Idaho, in November, when authorities began searching for JJ and Tylee. It appears now that Vallow and Daybell have been staying on Kaua'i, though it is unclear how long the couple has been on the island.

Rexburg police believe the couple may have information that could help locate the children, and accused them of fleeing and not cooperating with the investigation.

Read More