Verizon says the effects of Superstorm Sandy on its fourth-quarter earnings could be "significant."

Verizon Communications Inc., whose downtown Manhattan facilities were flooded and are still without power, said Friday it is working to restore communications services to customers affected by the storm.

The New York-based company says this could take some time.

Sandy knocked some cell towers out earlier in the week but by Wednesday they were slowly coming back to life. But ongoing power outages mean many are still disabled.

Verizon says it is not possible to estimate the precise impact of the storm on its fourth-quarter results though it could be significant.

Its shares dropped 54 cents to $44.60 in premarket trading.