A mail carrier driving her route while allegedly extremely drunk along a busy Minnetonka street crashed into a street sign, police said Tuesday.

Mary E. Sweet, 59, registered a blood-alcohol level of 0.297 percent in a preliminary breath test at the scene late Friday morning, police said. She was jailed and charged with third-degree drunken driving. “A witness saw her vehicle on Excelsior [Boulevard] almost strike another vehicle,” said Police Chief Jeff Sebenaler.

Soon after, Sweet turned onto Clear Spring Road near a public library and crashed into a stop sign, Sebenaler said. She was not hurt.

Sweet failed a field sobriety test before having her blood-alcohol level measured at nearly four times the legal limit in Minnesota.

The driver’s route was completed by other personnel, said U.S. Postal Service spokesman Pete Nowacki.

Hired by the Postal Service in May 2014, Sweet “has been placed in a non-duty status pending the results of an investigation,” Nowacki said.

Sweet was released from jail three days later and has a late May court date. She was not available Tuesday to respond to the allegations.