State transportation officials say traffic on a main route between northern New York and Vermont will be reduced to one lane for four to eight weeks while work is being done to repair damage from a rock slide last month.

Officials say traffic will be controlled by alternating signals on both ends of the closure on Route 4 in Fort Ann, New York starting today. The closure is between Kelsey Pond Lane and Route 22.

Workers are removing additional rock from the slope involved in last month's massive rock slide. There may be temporary closures of both lanes as blasting is done.

The cliff collapsed on Oct. 15, sending 2,000 tons of rocks and boulders onto 200 yards of roadway. The falling rocks narrowly missed several vehicles.