An 18-year-old motorcyclist was killed in a high-speed illegal race along Interstate 59 in Ft. Payne, Ala. Monday morning, authorities say.

Joseph C. Blackwell of Fort Payne reached speeds in excess of 150 mph while racing Jonathan A. Farmer of Section, Ala., between Ft. Payne’s two I-59 exits, said police commissioner Ron Ogletree. Mr. Farmer’s exact age wasn’t available, but he is in his 20s, Mr. Ogletree said.

The men had already raced from south to north between exits 218 and 222, said Mr. Ogletree. On the return north-to-south race, the two men merged left to avoid a tractor-trailer traveling around 65 mph. That’s when Mr. Blackwell struck the left corner of the truck.

His Suzuki motorcycle flipped multiple times. He was dead when help arrived. His friend, Mr. Farmer, was injured when he tried to stop his bike to help. His injuries were not life-threatening, Mr. Ogletree said.

“At those speeds, you need to be extremely aware,” Mr. Ogletree said. “Traveling at nearly two-and-half times the speed of the truck, he just couldn’t react fast enough.”

No charges will be brought against Mr. Farmer in light of his friend’s death, Mr. Ogletree said.