A McDonald's employee in Pittsburgh was arrested for putting a little something extra in their Happy Meals - heroin to be exact, police said today.

By sending a text message and uttering a secret code, "boy's toy," at the drive-thru window, a customer could get their hands on a Happy Meal, complete with a SpongeBob SquarePants figurine, with a side of heroin from a McDonald's in the East Liberty neighborhood of the city, police said.

Shantia Dennis, 26, was arrested after a drive-thru drug bust on Wednesday afternoon, police said.

After an informant tipped off authorities, undercover officers from the District Attorney Narcotics Enforcement Team set up a drug buy, police said. The officers "watched as Dennis placed a bundle of stamp bags into a Happy Meal box and handed it out to us" after they pulled up to the first drive-thru window as instructed, according to the criminal complaint.

Dennis put $80 in her bra, rung up the toy for $2 and handed over the Happy Meal, police said.

Pittsburgh Police Department

After the deal was done, officers moved in and placed Dennis in custody, according to the criminal complaint.

Swissvale Police Department Chief Greg Geppert told ABC News that Dennis was arrested and taken into custody with her McDonald's uniform on.

Aside from the $80 in her bra "that matched the serial numbers of the official funds used to conduct the buy," Dennis had an additional $80 and a small amount of marijuana hidden in her bra, Geppert said.

"There was $160 total, leading you to believe she did another $80 deal" prior to the bust, Geppert said.

Upon her arrest, "Dennis asked that we bring her purse with us as we escorted her out of McDonald's," according to court documents, and in it was "an additional brick of heroin marked with the stamp 'Nite Nite Niga.'"

That brick amounted to another 40 to 50 bags of heroin, Geppert said.

Dennis is currently being held in the Allegheny County Jail with bond set at $30,000, Allegheny District Attorney spokesman Mike Manko told ABC News today.

She has yet to post bail, Manko said, noting that Dennis will face a preliminary hearing on Feb.11 at Pittsburgh Municipal Court. "I am not aware of any counsel for her yet," Manko added.

So far, Dennis faces charges of possession with intent to deliver, "which she did deliver," Geppert said.

Pittsburgh Police Department

"It is unknown at this point how long this process had been going on or how many like transactions may have taken place prior to today," the DA's office said in a statement.

Iftikhar Malik, the owner/operator of that McDonald's franchise, released a statement saying: "As an employer and a member of the community, the safety of our guests and employees is our first priority. The allegations related to this employee do not represent acceptable behaviors and are not consistent with my values. As such, we take these charges very seriously and we are fully cooperating with the authorities. We are also conducting our own thorough internal investigation."

This is the second time this month police have made a drug-related arrest at a McDonald's franchise in Pennsylvania. Theodore Levon Upshaw, 28, was arrested just two weeks ago and is charged with dealing heroin out of the Murrysville McDonald's on Route 22, police said.

McDonald's corporate officials said in a statement that they are "concerned and together with our franchisee, are actively engaged in the investigation. The alleged behavior is completely inappropriate and does not reflect our values and the priority we place on the safety of our customers and restaurant employees."

It is not known whether the East Liberty case has any connection to the Murrysville case, according to reports by ABC News' Pittsburgh affiliate WTAE.