Four motorcyclists were killed in collisions with other vehicles Friday, in a grim beginning to the final weekend of the 89th annual Laconia Bike Week, state police said.

Cyclists were killed in Nashua, Nelson, Laconia and Dummer in a series of accidents within a four-hour span that began in early afternoon.

Two New Hampshire men, Michael Loverme of Merrimack and Jamie Bezanson were among those killed, along with motorcycle riders from New York state and Connecticut.

At 12:39 p.m., a car driven by James Rivadeneira of Salem crossed the double yellow line on Route 9 in Nelson, colliding with a motorcycle driven by David Davis of Wyantskill, N.Y. Davis' motorcycle then hit a second Harley-Davidson cycle driven by Carl Davino of Stuyvesant, N.Y.

Davis was taken to Cheshire Medical Center in Keene where he died of his injuries. Rivadeneira and Davino were treated for non-life-threatening injuries at Cheshire Medical Center.

Police are asking for help from the public in their investigation into the Nelson accident. Anyone with information is asked to call Trooper Michael Anger at New Hampshire State Police Troop C at 223-8740,

Two other fatal accidents happened within minutes of each other in Laconia and Dummer.

At 3:03 p.m. on Rollercoaster Road in North Laconia, a motorcycle driven by Jamie Bezanson, 38, of Concord, crossed the center line and hit the driver's side of a pickup truck driven by Craig Harrison, 47, of Manchester.

Bezanson was pronounced dead at the scene of the crash by the New Hampshire Medical Examiner's office.

Harrison was treated for minor injuries at Lakes Region General Hospital and released.

A short time later, at 3:15 p.m, a Connecticut man was killed in a crash on Dummer Pond Road in the town of Dummer.

State police investigators said a Hyundai Elantra, driven north on Route 16, driven by Ashley Bailey, 25, of Jay, Maine, crossed the double yellow line into the southbound lane. The Hyundai collided with the Harley-Davidson motorcycle driven by Thomas Zappulla, 60, of Torrington, Conn. Zappulla was thrown from the motorcycle and pronounced dead at the scene.

Bailey was taken to Androscoggin Valley Hospital in Berlin and was in stable condition with what police termed serious injuries.

State police are investigating to determine why Bailey's vehicle crossed the center line on the roadway.

At 4:15 p.m., a Merrimack man was killed when his vehicle collided with several vehicles after crossing the median strip, police reported.

The motorcyclist, identified at Michael Loverme, 24, of Merrimack, was on the Exit 8 on-ramp to the F.E.Everett Turnpike when the motorcycle traveled across the median and entered the travel lanes where it was hit by the other vehicles.

Loverme was taken to Southern New Hampshire Medical Center in Nashua where he was pronounced dead.

The crash caused massive traffic tie-ups at the height of the afternoon rush hour.

Police diverted northbound traffic off the highway at Exit 8, where drivers were directed over an overpass to rejoin the highway. Traffic on the turnpike was limited to the high-speed breakdown lane for about two hours until the high-speed lane could be reopened. Traffic was restricted in the area for about four-and-one-half hours while the State Police Accident Reconstruction Unit investigated.

wsmith@unionleader.com