PHILADELPHIA — The U.S. Postal Service could close 11 mail processing facilities in Pennsylvania under a proposal that would slow mail travel and eliminate next-day deliveries.

The facilities slated for closure are mostly in major population centers across the state, including Pittsburgh, Scranton, Reading, Erie and Altoona.

The cash-strapped USPS is trying to cut $3 billion in costs while it struggled to avert bankruptcy amid increased competition that has seriously dented the amount of mail it handles.

The proposal would also close processing and distribution operations in Lancaster, New Castle, Williamsport and Chester County. Postal Service spokeswoman Cathy Yarosky said the distribution facility in Horsham was originally proposed for closure but has since been taken off the list.

Under the proposal, the targeted facilities could be closed as early as next March.