MOTT HAVEN, the Bronx — Update: The schools will reopen Friday; more info here.

Two co-located schools in the Bronx are being closed Thursday after a student tested positive for COVID-19, according to Mayor Bill de Blasio.

According to the mayor, the Laboratory School of Finance and Technology and the South Bronx Preparatory: A College Board School are being closed. Both schools are located in the same Mott Haven building.

Both public schools serve students in grades 6 through 12.

A student self-confirmed they tested positive for the novel coronavirus, de Blasio said. The NYC Health Department will be tracing close contacts of the student and recommend quarantine and testing as necessary, he said.

Anna Ramos, the mother of an 8th grade girl who attends South Bronx Preparatory, called into the PIX11 Morning News to explain what happened when her daughter got to school Thursday morning. Watch the phone interview above in full.

Ramos said when she called the school she was told the COVID-19 case was not at South Bronx Preparatory but that both schools were evacuated and closed out of precaution, as the two schools are located in the same building.

De Blasio confirmed the Department of Education will completely disinfect the building and it will be closed for an initial 24-hour period.

"We don’t make this decision lightly, and we know the disruption and anxiety this means for students, faculty and parents," the Mayor said in a statement. "We are taking every precaution to keep people safe, and we will keep everyone informed as we learn more through the day."

The news comes the same day New Rochelle's one-mile containment zone goes into effect in Westchester County, and just a day after Mayor de Blasio officially postponed New York City's annual St. Patrick's Day Parade.

See a full list of New York and New Jersey school closures and partial closures due to coronavirus.

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