Verizon says it is working with the FBI to investigate nearly 100 incidents of phone line sabotage as the union strike reaches its fifth day.

According to Verizon officials, their crews have encountered acts of sabotage against network facilities across the Northeast, including fiber optic and phone lines in Pomona and Harriman State Park being deliberately cut.

More than 45,000 Verizon workers from New York to Massachusetts began the strike after contract negotiations broke down over the weekend. They claim that Verizon is asking for too many contract concessions, including contributions to employee pensions and health care.

Verizon has also obtained injunctions preventing picketing workers from intimidating customers and illegally blocking access to its facilities.

Union leaders are denying all of the company's claims.

Verizon claims 12 acts of sabotageVerizon workers strike after contract negotiations fall through