A federal judge has ruled that two ordinances passed by a Western Pennsylvania township to prohibit mining were invalid.

Penn Ridge Coal and Allegheny Pittsburgh Coal sued Blaine Township last year, alleging that the local laws were unconstitutional.

Chief U.S. District Judge Donetta Ambrose agreed in an opinion issued Wednesday.

The township, in an attempt to protect the local environment, passed two ordinances to try to stop mining and drilling there.

Allegheny Pittsburgh owns about 11 million recoverable tons of coal reserves in the township, and has leased the mining rights to Oklahoma-based Penn Ridge.

Police believe G-20 protest pipes found

Pittsburgh police say they've found PVC pipes that resemble a device used by protesters to blockade streets.

Police say about 60 feet of PVC pipe found early Thursday in the city's Lawrenceville neighborhood had been cut into several sections and chained together with multiple holes in the top. Police say the pipes also had nails jutting through them.

Police are concerned the protesters at next week's G-20 summit may use PVC pipes for a tactic called a "sleeping dragon." In that tactic, protesters handcuff themselves to each other and have their hands inside pipes to make it harder for police to cut the handcuffs.