“Keeping Up With the Kardashians” star Rob Kardashian is a suspect in a criminal threat investigation, TMZ wrote in an exclusive report Thursday. He allegedly threatened someone who is close to his pregnant fiancée, Blac Chyna.

Kardashian, 29, is accused of threatening Pilot Jones with physical harm. Jones, an actor who has been on the TV show "Glee," was linked to Chyna, 28, after a picture of them kissing was leaked by Radar Online Sunday.

Kardashian allegedly threatened Jones through text messages, saying things like, “Leave my wife alone. I'm not playing with you.”

But that’s not all. In some of the texts, he supposedly said there would be physical harm involved if Jones didn’t stay away from Chyna. Those messages, however, are “a little murky and general,” a source told TMZ.

The threats are being investigated by the Los Angeles Police Department.

The make out photos were supposedly taken in March when she went on a trip to Atlanta to see Jones. At the time, she and Kardashian were reportedly on a break. Jones and Chyna are “great friends,” his rep told Radar Online Sunday.

Chyna and Jones “kissed and made out every time they saw each other,” an insider told Radar Online Sunday. “They even started to develop feelings too!” The source added: "It was a flirty type of relationship, and they hung out every day."

While the apparent fling seems shady, Jones reportedly didn’t know Chyna was involved with Kardashian. “Pilot had no idea she was talking to Rob too until it all became public,” the source said.

At the end of the “Rob & Chyna” series, the reality star said she wanted to take a paternity test to make sure the baby was Kardashian’s. “This might sound f---ed up but a part of me wants to take a paternity test,” she told her friends on the finale Oct. 16. “I know it's Rob's child, I've only been with Rob since we started dating. It's just to shut down rumors on the internet saying that it might be two other people.”

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