Police and social services in Silicon Valley are starting a massive cleanout Thursday of what’s likely the nation’s largest homeless encampment.

Animal control and a construction contractor are also helping dismantle the square-mile site that once was home to more than 200 homeless residents, San Jose homelessness response manager Ray Bramson said.

People living in the camp, known as The Jungle, were told Monday they must be out by Thursday or face arrest for trespassing. The encampment stands in stark contrast to its surrounding area in the heart of the Silicon Valley, a region leading the country for job growth, income, innovation and venture capital.

In a walkthrough earlier this week, officials found there were 60 people left in the camp. They didn’t know how many remained after Monday.

Officials will try to find people who have been involved in social services some kind of shelter for the night. Bramson says those not involved in social services “are going to have to leave today anyways.”

There have been no reports of violence or people refusing to leave.

The first thing the team will do is go through the hand-built structures and tents looking for cash, IDs or anything else of value. Those items will be sorted and stored for people to claim later.

In the past year and a half, the city of San Jose has spent more than $4 million on solving the problems at the encampment.

The last camp cleanout was in May 2012 when about 150 people were moved out of The Jungle.

Bramson said earlier this week that increased violence, wet weather and unsanitary conditions make it imperative the camp is cleared. In the last month, one resident tried to strangle someone with a cord of wire down there, he said. Another was nearly beaten to death with a hammer.