Officials said the "very serious accident" happened on King Street.
Police said nine people were aboard the minibus: 7 developmentally disabled adults, a monitor, and a driver. The school bus had only the driver on board.
Ten people, all adults, were taken to Stamford Hospital, and all are in fair condition. The most seriously injured is one of the bus drivers.
The school bus belonged to Sacred Heart Greenwich, which is near the scene of the accident. It was either arriving to pick up students or had just dropped students off.
The minibus was from Countywide Transportation based in Yonkers. The adults on board were being taken from their day rehabilitation program back to group homes and residences in northern Westchester.
Police tweeted a photo from the scene, showing a totaled minibus and debris scattered across the street.
Traffic Advisory: in the area of 1252 King Street is completely closed for very serious accident. This will be an extended road closure for the investigation @GWCHFreePress @GreenwichTime @GreenwichPatch @gwchsentinel @News12CT pic.twitter.com/gtgk8nZGD7— Greenwich PD PIO (@GreenwichCTPD) April 9, 2019
Greenwich Police said King Street is closed in both directions near the Brunswick School and will be for an extended period of time.
Police are currently investigating.
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