Police in riot gear order 'Occupy Wall Street' protesters to leave park

WATCH LIVE: Evicted occupiers take to the streets

Hundreds of police officers in riot gear descended on the "Occupy Wall Street" demonstration in New York City's Zuccotti Park not long after midnight Tuesday.

Police handed out letters to protesters ordering them to immediately remove their possessions from the park. The letter claimed that the demonstration posed a health and fire safety hazard, and would be cleaned after the protesters left.

"If you fail to immediately leave the park, you will be subject to arrest," the letter said.

Once work in the park is complete, the demonstrators can return to the park but cannot bring back tents, tarps or sleeping bags, according to the letter.

"Liberty Square (Zuccotti Park), home of Occupy Wall Street for the past two months and birthplace of the 99% movement that has spread across the country and around the world, is presently being evicted by a large police force," the demonstrators said in a statement.

Police surrounded the park and refused to allow anyone in, including reporters.

While some of the protesters gathered their belongings and left, a core group rallied near the center of the park and refused to leave, according to the New York Times. They chanted, "Who's park? Our park! No retreat. No surrender!"

Meanwhile, dozens of officers walked through the park, removing tents and other materials.

Fifteen people were arrested for disorderly conduct and resisting arrest, according to Police spokesman Paul Browne.

The eviction comes as the "Occupy Wall Street" demonstration against economic inequality neared its two-month anniversary. The protesters had planned a provocative "day of action" to shut down Wall Street.