WASHINGTON, Feb. 14 (Xinhua) -- There are "a number of fatalities" in a school shooting in the U.S. state of Florida, said a U.S. senator on Wednesday.

There is more than one fatality, or even many in the shooting, Senator Bill Nelson from Florida told CNN.

At least 20 people were wounded in a shooting at Marjory Stoneman Douglas High School in Parkland, just north of Miami, according to local media.

"Shooter is now in custody," said Broward County Sheriff on its twitter account.

Students were seen running from the school, while emergency responders have arrived on site to deal with the situation.

The White House Press Office said in a statement "the President has been made aware of the school shooting in Florida. We are monitoring the situation. Our thoughts and prayers are with those affected."

Florida Senator Marco Rubio said in tweet that he is monitoring the "horrible unfolding situation."