TRAVERSE CITY, Mich. (AP) - Authorities raided 17 Chinese restaurants around Michigan that they suspect of ducking millions of dollars in taxes and importing undocumented workers as a ``modern version of indentured servants.''

Search warrants were also served at 21 homes of suspected undocumented Chinese workers. Dozens were involved in the scheme, State Police Lt. Curt Schram said.

``It cost them X number of dollars to come to this country and they're trying to work off that debt,'' Schram said.

Investigators believe one family or related families own the restaurants, which are mostly in the central and west-central areas of the Lower Peninsula, the statement said.

Nearly 20 workers were living in one house with ``very spartan'' furnishings in Grand Rapids, Schram said.

The owners are suspected of claiming only a third of their actual income and sending part of the proceeds out of the country, while shortchanging the state and federal governments of millions of dollars in sales, unemployment and use taxes, police said. About $400,000 in cash was seized.

Nine people were arrested at a Chinese buffet in Petoskey, and two people believed to be undocumented workers were charged with driver's license violations and jailed in Montcalm County. An additional 13 people were found to have deportation orders and were handed over to immigration authorities.

``It's some sort of modern version of indentured servants,'' Emmet County Prosecutor James Linderman said.

A message seeking comment was left Thursday on the Petoskey restaurant's answering machine.

The investigation began with one detective checking out a report in Newaygo County and eventually involved 22 local, state and federal agencies, Schram said.

Businesses in other states also are being looked at, although warrants have been served only in Michigan, he said.

The raids turned up ``a tremendous amount'' of business records written in Chinese that must be translated, Schram said.