UPDATE: Exit 20 off-ramp back open after serious crash in Charlestown

Boston Police responded to a serious crash on Alford Street in Charlestown prompting road closures Wednesday afternoon.

Police responded to the crash on Alford St., Sullivan Sq., just after 3 p.m. and said there are life-threatening injuries. There has been no information regarding how many people were involved in the crash.

MassDOT said just after 7 p.m. that Exit 20 off-ramp is back open after hours of delays.

No further information has been released.

This is a developing story. Check back for updates as more information becomes available.

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