PORTLAND — A warning of possible storm-related service outages from leaders of a union strike at FairPoint Communications prompted a sharp response from company officials Tuesday, who alleged union members have harassed the workers hired to replace them during the strike.

The unions warned early in the day that a nor’easter storm expected to bring winds and rain to Maine through at least Wednesday could mean increased service interruptions as FairPoint is relying on replacement workers to maintain the company’s networks.

In a return salvo, the company said its contingency plans are in place and alleged that some union members have harassed replacement workers crossing the picket lines.

The company statement added that the volume of calls to its customer service centers has been higher than usual and that a large number of the calls “appear to be computer-generated,” but it did not outright accuse union officials of jamming its phones.

Angelynne Beaudry, a spokeswoman for the company, said in an email that FairPoint has been in touch with “appropriate authorities” about the allegations.

A union representative said Tuesday night that leaders were drafting a response to those charges.

In its earlier statement, members of the International Brotherhood of Electrical Workers and Communications Workers of America questioned whether the replacement workers would be prepared to handle local challenges posed by a storm.

“We know exactly where the trouble spots are — where back-up batteries are weakest and where phone and DSL lines are most likely to go down — so we’d jump in our trucks and head to those spots first,” said Chris Whidden, a Lewiston-based service technician. “Some inexperienced replacement worker from down south isn’t going to know where to go — and also isn’t going to know our back roads or be able to navigate easily in the dark. If a tree blocks Dyer Road, he won’t know how to find another route to get the backup generators where they’re needed.”

FairPoint said it expects its contingency plan will be in place shortly and is preparing for the storm this week.

“As our managers, non-union employees and contingent workforce ramp to capacity to address the needs of our customers, we are deploying all available resources to prepare for and respond to any storm related impact,” the statement indicated.

Intense weather conditions are expected to last through Friday, according to the National Weather Service.

According to Pete McLaughlin, a lead negotiator for the International Brotherhood of Electrical Workers in talks with the company, FairPoint is the largest owner of utility poles in the state. Those poles hold its service lines for telephones, its fiber-optic cables and DSL lines and also are leased to other service providers such as Time Warner, Oxford Networks, GWI and power companies.

Similarly, the company’s strike has raised concern from police departments as FairPoint separately manages a statewide 911 call dispatch system. Tom Welch, chairman of the Maine Public Utilities Commission, said last week that the PUC is monitoring that system daily and that the commission has the authority to take action if there are other service problems on the company’s telephone lines. The PUC does not regulate the company’s Internet service or the 911 system.

For the 911 service, it has a contract with the company, which Welch said would allow the PUC’s Emergency Services Communication Bureau to act immediately in the event of a problem.

The two unions, representing about 2,000 workers in Maine, New Hampshire and Vermont, have been on strike since Friday. There are about 800 workers on strike at FairPoint offices across the state.