The Stamp Student Union was evacuated yesterday morning after a small grease fire broke out at the McDonald’s restaurant, witnesses and fire officials said.

The student union’s fire alarm went off 8:30 a.m., witnesses said. Prince George’s County Fire Department spokesman Mark Brady said an automatic fire extinguisher put out the fire in the restaurant’s kitchen, and fire officials re-opened the building within 20 minutes.

Damage was limited to “the food that was cooking at the time,” Brady said, but the McDonald’s was still closed until about 3:30 p.m.

Sapienza Barone, an assistant to university President Dan Mote, said she had been in the student union preparing for yesterday’s textbook summit when the fire alarm went off, but she described the interruption as “no big deal.”

“Better to be safe than sorry,” she said of the evacuation.

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