Two South Dakota men are facing charges, accused of trying to have sex with teenage girls.  Police caught both during internet stings where an undercover officer posed as the girl.

They arrested 25-year-old Brian Bublitz of Altamont, which is just east of Watertown, a week ago for solicitation of a minor after an eight-month long investigation.

Then Friday, they arrested 30-year-old Mathew Chamberlain of Brandon on the same charge after a two-week investigation.  And according to court papers in the Chamberlain case, this isn't the first time Chamberlain has tried to prey on young children.

Mathew Chamberlain walked to court Monday after being arrested at his Brandon home on Friday. Police say he never actually tried meeting the girl but they say that doesn't matter. 

"It's not necessary to have that face-to-face meeting or have the suspect try to meet with the detective for this crime," officer Sam Clemens said.

The evidence, they say, is in court papers. They say on May 29, Chamberlain began chatting with an undercover officer who he thought was a 15-year-old girl.  After a short conversation, Chamberlain asked her if she was a virgin and if she wore thongs.

Then the conversation moved to their cell phones where Chamberlain texted her saying he had "a dirty pic of himself" and asked her if "she wanted to see it?"

The papers say when he sent it, he asked "if she liked it?"

He also sent her an inappropriate video of himself and told her not to show any one because "I don't want to go to jail."

Then on June 3, Chamberlain asked the girl when they could meet. She replied, "We could meet at the mall sometime, are you cool with that?"

No meeting ever happened. On June 5, Chamberlain began chatting with the undercover officer again and this time asked her if she "wanted to get drunk some time?" He said, "Then we could get naked and have some fun."

It's been a year since police made their last arrest like this. They say two in one week is unusual, but they're sure it won't be the last. 

"That's one of the reasons they're doing this.  They know there's predators out there and so we're doing this trying to keep the kids safe," Clemens said. 

In 2002, Chamberlain was charged with sexual intercourse without consent in Montana. He later pled guilty to a misdemeanor charge of Endangering the Welfare of a Child.

If convicted, both Chamberlain and Bublitz could get two years in prison.

If you'd like to read the court documents in detail, click here