UPDATED 06/08/12 9:13 a.m.

SOUTH HOLLAND, Ill. (CBS) — Illinois State Police have closed the Lincoln Tollway Oasis on the Tri-State (I-294), as they investigate an armed robbery.

State police shut down the entire Chicago Southland Lincoln Tollway Oasis around 2:45 a.m. for the investigation.

An armed suspect robbed the McDonald’s at the oasis and made off with an unknown amount of money, state police told CBS 2. No one was injured.

The oasis remained closed as of 9 a.m. Friday. It was not known when it would reopen.

WBBM Newsradio’s Bernie Tafoya reports the only accommodation that is open at the oasis is the Mobil gas station accessible to southbound traffic.

State police said as of 8:45 a.m., no one was in custody.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

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