CLINTON, Mass. (AP) — Hot air balloon passengers injured in a crash over the weekend in Massachusetts have been released from a hospital.

The Federal Aviation Administration says two people stayed overnight at the hospital for treatment after the balloon crashed Saturday night into power lines while trying to land in a residential area in Clinton, an hour’s drive west of Boston. Four of the seven passengers suffered injuries.

Witnesses say there was a huge explosion when the balloon hit the power lines.

The FAA said Monday it’s still investigating the crash.

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