Beginning Friday, 11 additional Massachusetts State ­Police patrols will cruise Route 24 and Interstate 195 every weekend for the rest of the summer as law enforcement officials attempt to counter an increase in traffic fatalities and injuries.

The extra patrols, which will run from 8 p.m. to 4 a.m. Friday and Saturday nights, are in response to a number of recent crashes and will cost about $125,000, according to State Police.

Previously, there have been only three State Police cruisers on those roads during the same hours.

Six people have been killed in crashes on Route 24 so far this year, compared with five traffic fatalities on that highway in all of 2011, said David Procopio, a State Police spokesman.

Three of those fatalities ­occurred this month.

Angel Pina, 12, of Norton was killed July 12 when the truck she was riding in rolled over after one of its back tires blew out. She was ejected from the truck.

On July 15, Lisa Banat, 19, of Mansfield was killed when her car, traveling the wrong way on Route 24, struck a pickup truck head-on around 4 a.m. The truck’s driver, John LaChapelle, 44, of Tiverton, R.I., was also killed when his vehicle burst into flames.

“One death is one death too many,” said Procopio, who added that most of the fatal accidents have occurred during the late-night and early-morning hours of the weekends.

Nearly 40 percent of the ­fatal crashes on these roads this year were caused by drivers impaired by drugs or alcohol, Procopio said. Other accidents were caused by speeding and distracted driving.

The Massachusetts Department of Transportation is finishing a $12 million resurfacing project on much of Route 24, and the fresh roadway may tempt some drivers to speed, Frank DePaola, highaway ­administrator, said at a press conference Thursday.

More than 100,000 drivers travel Route 24 each day, said DePaola.

State Police will re-analyze crash statistics at the end of the summer to determine if it is necessary to continue the extra patrols. “If we can make the roads safer, this will be ­invaluable,” Procopio said.