AURORA | An FBI agent testified Wednesday she found a Batman mask inside James Holmes’ apartment after he opened fire during the midnight premiere of “The Dark Knight Rises” in July 2012.

Stephanie Benitez said the mask was one of dozens of items of evidence seized from Holmes’ booby-trapped apartment on Paris Street.

“It was prominently displayed on the television stand in the living room,” she said, adding that the mask had Holmes’ fingerprints on it.

FBI agents also seized flashlights, gloves, shoes and tactical mirrors from the apartment, Benitez testified Wednesday.

Benitez testified there was a very strong smell of gasoline in the apartment during the search. “We put on masks toward the end of the search because of the fumes,” she said.

The jury asked Benitez what evidence submitted as black tanks contained. She responded the black tanks were pressurized, but she was not sure what was in them. The jury then proceeded to review evidence submitted by Benitez.

Around 10 a.m., postal inspector and former Aurora police officer Greg McGahey took the stand. He testified about the package Holmes mailed to Dr. Lynne Fenton, which included the notebook the jury read Tuesday.

He said the package would have been mailed the night before July 20, 2012, according to when it was processed by the U.S. Postal Service. He said a book of forever stamps were sold as part of the same transaction.

After McGahey, Jansen  Young, a veterinary technician who was in the theater the night of the shooting, testified. Young said when she saw a canister fly over her head in the theater and smelled smoke, she thought teenagers were playing a prank.

She was with  Jonathan Blunk that night who was killed.

She described Blunk pushing her underneath the seat after the canister was thrown.

“I was laying flat underneath the seats, and he was on my left side,” she said. Young then said she heard gurgling sounds coming from Blunk. She heard the gurgling three times before it stopped.

She said she then felt “warm wet stuff” flowing from the seats above her.

“I decided this was a prank again. It had to be water balloons with warm wet latex. It was like a river of water falling onto me. I was blinking this liquid down my eyes,” she said.

When the shooting stopped, she said she shook Blunk, whose face was turned toward her. He was not moving or breathing. She said she could barely lift Blunk,  who was 6’2” and around 200 pounds.

Young crawled to the end of the seats, and ran down the stairs to try get help. She was afraid to exit through the lobby, so she exited through another part of the theater.

She said she saw a white car outside with someone standing next to it. She said the individual looked like a man and was “weirding her out.”

She hid underneath a trash compacter, so that the person near the car couldn’t hear her, she said.  Young had incurred a shrapnel wound on her left side from the shooting.

Prosecutors say Holmes killed 12 and wounded 70 others during the attack. He has pleaded not guilty by reason of insanity.

While Holmes opened fire during a screening of “The Dark Knight Rises,” there have been few mentions about why he chose that particular movie. On Wednesday, during discussion about Holmes’ notebook, it was revealed he wrote “Embraced the hate, the Dark Knight Rises,” in the it, along with plans for the attack and details about his mental state.