Waltham Teen Told Police He Was Held Hostage Before Stabbing: Court Documents

WALTHAM, MA — More information is unfolding in the case of the teen charged with murdering a woman on Adams Street last weekend following his arraignment.

Derrick Lopez, 18, of Waltham was arraigned Monday in Waltham District Court in connection with the death of Christin Tobin, 36, of the unit block of Adams Street last weekend. Lopez was charged with murder and held without bail.

About 2:39 a.m. on July 15, two men flagged down a police cruiser in front of the Adams Street address then decided they didn't have anything to say. It took a minute before one of the men told police that his cousin, later identified as Lopez, was inside the rooming house with a woman who had locked him inside. The cousin said something about three cell phones, but before the officer had the chance to figure out what he meant, the cousin's phone rang.

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Officer Aucoin said in his police report he heard the man say into the phone, "What happened? You did what? You stabbed her?"

The cousin turned the phone around and showed the officer the name on the phone was Lopez's and told police he was now down the street near the intersection of Crescent and Maple streets at the Super Petroleum, which is about a 4-minute walk.

Aucoin called for backup, and he and the cousin made their way into the boarding house, kicking down a door in the process.

When they forced her way into the apartment, the woman, Tobin, was found dead in a pool of blood right in front of the door with what appeared to be stab wounds. The studio apartment was in disarray, and there was blood in various parts of the apartment, according to the police report.

Shortly after, Lopez approached police officers and told them he was the one who had stabbed the woman on Adams Street, according to court documents.

Lopez told police in an interview he and his cousin were walking down Adams Street when he had to use the bathroom. He said he saw a woman he did not know on the the porch of the home and asked her if he could use her bathroom. She agreed and brought Lopez inside the rooming house and up the stairs. Lopez went to the bathroom that was in the hallway, and when he was walking out of the bathroom she grabbed him and forced him into a room. He told police she then closed the door and took both his cell phone as well as another man's cell phone and put them in her bra. He said she then took out a pocket knife and threatened him with it.

Lopez said the woman held him hostage for more than two hours while she smoked crack, according to court documents. During that two-hour span his cousin called him, he said, but he told his cousin everything was OK and he'd be down later. Lopez said his mom also called him and urged him to come home, to which he told her he'd be home shortly. According to the court documents at least one of these conversations happened on speakerphone.

At some point while the woman was sitting down Lopez demanded she return his cellphone. Police asked him if this was frustrating, to which "he stated that he was mad, so mad. He stated that he was as angry as he has ever been," according to the court documents.

Then, he told police, the woman picked the knife back up. Lopez told police he yelled at her and that she was slightly laughing.

"I looked at her dead in the eye, I have never been so mad before, like in my life," he told police. It was just after that police said he told them she tried to attack him, and he grabbed the knife from her and began stabbing her. He told police it felt like he was in a dream.

After this he said he found the phone from the floor, checked the woman and found she wasn't breathing and left, walking down to the river, and then decided to tell police what happened.

Police noted that Lopez told them he blacked out a few times during the incident, but when they asked him about things that happened during that time he was able to answer with detail.

Police said the murder is still under investigation. Court documents show that there were nine individuals involved, including one witness ranging in age from 27 to 72.

RELATED: Lopez Charged With Murder

UPDATES to come.

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Photo of the Waltham District Court sign and the rooming house where the woman was found dead and the gas station where Lopez allegedly told his cousin he was following the incident by Jenna Fisher/Patch

Information from this report comes from court documents