EXCLUSIVE: The Truth About Ben Affleck and Jennifer Garner’s Secret Reunion Revealed After Pair Were Caught in Intimate Clinch – ‘His Hug Was Not Something you Do With an Ex….See More

Flirty exes Ben Affleck and Jennifer Garner are said to have finally crossed the line from best friends forever to a lot more.

An eyewitness caught Affleck on camera holding Garner in a steamy romantic clinch – and her longtime boyfriend, John Miller, was nowhere in sight, RadarOnline.com can reveal.

According to the onlooker, the 52-year-old Oscar winner clutched the Yes Day cutie, 52, around the waist while rubbing his pelvis up against her and putting his lips near her ear.

The two, who were married for 10 years, were celebrating son Samuel’s 13th birthday at a paintball park.

Ben and Jen looked like they were having a ball,” an insider told us. “They were giggling and joking and having a great time. Sparks definitely flew.”

Another Hollywood insider added: “The question is what this means for Jen’s relationship with John. He can’t be happy to see Ben hugging his girlfriend.”

Body language expert Patti Wood told RadarOnline.com Affleck’s lovey-dovey posture “communicates his desire to be sexually intimate or familiarity with her based on their old relationship.