The Israel Defense Forces warned residents in Gaza not to approach IDF troops "until further notice," IDF Arab media spokesperson Avichay Adraee said in a Friday X post.

"Approaching the forces puts you at risk," Adraee said in the post.

"These are moments of heightened alert," IDF spokesperson Effie Defrin said during a briefing with reporters Friday, warning "IDF soldiers will act to remove any threat to their security," inside of Gaza along the redeployment lines where they are now positioned.

"At this time our troops under Southern Command have deployed to the agreed readiness lines, in accordance with this 'yellow line,' these readiness lines provide forward operational defense and control along the Gaza Strip," Defrin said.

-ABC News' Jordana Miller

The Israeli Defense Forces released videos showing forces redeploying inside of Gaza.

The IDF said they completed redeployment along the agreed-upon lines in the first phase of the ceasefire deal at 5 a.m. eastern time on Friday, less than 12 hours after the Israeli government approved the first phase of the deal.

Along these lines, the IDF controls more than 50% of the Gaza Strip.

-ABC News' Jordana Miller

A ceasefire is now in effect as of 12 p.m. local time on Friday in Gaza, according to the IDF.

"Since 12:00, IDF troops began positioning themselves along the updated deployment lines in preparation for the ceasefire agreement and the return of hostages," the IDF said in their statement. "IDF troops in the Southern Command are deployed in the area and will continue to remove any immediate threat."

The Israeli government approved the first phase of the ceasefire deal at 1:20 a.m. Friday local time in Israel, triggering the next series of steps under the deal.

Here's a look at what happens next, according to Israeli sources and a draft document of the agreement obtained by ABC News.

The Israel Defense Forces will withdraw and redeploy troops to agreed-upon lines within 24 hours of the Israeli government approving the deal. This means that the IDF will reposition by 1:20 a.m. Saturday local Israel time. Once the IDF redeploys to the agreed upon borders, the IDF will remain in control of more than 50% of Gaza during this phase of the deal.

Within 72 hours after the IDF completes redeployment to the agreed-upon borders, all hostages, living and dead, will be released and returned to Israel.

In exchange, more than 1,000 Palestinian prisoners will be released. That includes 250 prisoners and detainees held in the custody of the Israeli Prison Service, along with 1,700 residents of the Gaza Strip who were not involved with the Oct. 7, 2023, attacks but were arrested afterward, according to a draft document of the agreement obtained by ABC News.

Under the terms called for in the first phase, more humanitarian aid will also be allowed into the Gaza Strip -- but details on when and how are still unknown.

-ABC News' Jordana Miller and Ellie Kaufman