MILFORD — A Merrimack man died Tuesday night after his car struck a tractor-trailer on Route 101 head-on, but it’s still unclear why his vehicle crossed over into oncoming traffic.

Just before 7 p.m. on Tuesday, police, fire and ambulance personnel responded to the two-vehicle crash on the Route 101 bypass just west of Route 101A.

According to Milford polcie Capt. Chris Nervik, a 2003 Honda Accord driven by Erich Eger, 49, of Merrimack was traveling east when he crossed over the solid yellow line into the path of a Kenworth tractor trailer driven by Scott Sears, 52, of New Bedford, Mass.

Eger was pronounced dead at the scene. Sears was not injured.

The accident shut down Route 101 in Milford for five hours as emergency personnel cleared the scene and Milford’s accident reconstruction team assessed the site. Nervik said the accident is still under investigation.

Nervik said that speed and alcohol did not appear to be factors in the crash.

Anyone who witnessed the accident is asked to contact police at 249-0630.

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