LIVONIA, N.Y. (AP) — Authorities plan to resume their search for two snowmobilers who are believed to have broken through the ice on one of the Finger Lakes.

The Livingston County Sheriff's Office says they were alerted around 3 a.m. Sunday by a family member who said that two men in their 40s hadn't returned from a snowmobile outing on Conesus Lake.

Emergency crews found snowmobile tracks leading away from one of the snowmobiler's home on the northern end of the lake, located about 20 miles south of Rochester.

Searchers found two helmets before halting the effort around 6:30 p.m. Sunday. The search is expected to resume Monday morning. Police say an underwater robot equipped with a camera and sonar will be used in the search.