Jenelle tells TMZ ... David, his girlfriend and 3 other men took bolt-cutters Sunday night and cut off the locks to the gate at her North Carolina property. She says they drove up to her garage and broke inside, loading up all her motorcycles and other property on a trailer.

The "Teen Mom" star has surveillance video of the whole caper, which she says was in violation of a court order she got during their divorce, barring David from setting foot on the property.

David was clearly aware of the order, because he informed the local sheriff's department, and they sent a deputy to escort him while he recovered items.

Jenelle wasn't home at the time -- she's been living in Las Vegas with the kids -- but was able to talk to the deputy through her Ring camera. She angrily told the deputy David wasn't allowed to be there, and claimed he'd missed the deadline to collect his stuff.

Meanwhile, Jenelle's surveillance video shows David driving up to the property, and taking down one of her cameras.

The video also appears to show David and co. moving a motorcycle onto the driveway, and the deputy's car is nearby with its blue strobe lights on.

After the deputy spoke to Janelle, he called his sergeant, who confirmed David was only allowed to take work tools, and not the motorbikes. The deputy told David to put 'em back, and he did.

The sheriff's dept. tells us they got pics of the the work tools David was allowed to take -- and they advised him to get a lawyer if he wanted to get the bikes, or any other items, from Jenelle.

For her part, Jenelle's still pissed because David missed his deadline, and says she's going to take legal action against him and the cop.