A tractor-trailer jackknifed on I-91 in Enfield Thursday morning, slowing southbound traffic to a crawl just over the Massachusetts state line.
The accident occurred around 6:30 a.m., and closed all but the far left lane on the southbound side of the highway just past Exit 49.
By 8 a.m., the middle lane had opened; the right lane was still closed as wreckers worked to remove the disabled cab and trailer.
