An Altoona man is behind bars on charges he stalked and harassed his ex-girlfriend and monitored her movements for eight months with a GPS tracking device that police said he had attached to her vehicle.

Matthew J. McDonald, 45, of 2421 Fifth Ave., was arrested Tuesday by Altoona police on a list of charges that include felony stalking and multiple misdemeanor counts that include loitering and prowling at night, theft and criminal mischief.

According to the charges filed against McDonald, after his relationship with the woman ended in October 2018, McDonald allegedly started a campaign of harassment that included vandalism and theft, which culminated with his ex-girlfriend discovering a GPS tracking device on her vehicle on Nov. 25, 2019.

Police noted the device, a Spytec STI GL300, was taken off the bumper by officers and a subpoena for customer information on the device revealed it was registered to McDonald. Police said the GPS real-time tracker had been in use for eight months.

McDonald is also accused of sending the woman repeated text messages in which he indicates knowing her location as well as that of a man with whom McDonald had accused her of being romantically involved. McDonald started sending the messages on Nov. 11, 2018, and they continued on a regular basis until Nov. 16 of this year. In some of the messages, McDonald references a nickname only he used for his ex-girlfriend and in one message he identified himself.

In the messages, McDonald refers to his ex-girlfriend by derogatory names and demeans another man while also making comments about what she was doing and how she lived her life.

Police contend that along with the messages, McDonald also vandalized the woman’s car and stole two trail cameras she set up after she got a protection-from-abuse order in December 2018 as well as security cameras she set up outside her home in June.

On Nov. 11, 2018, the woman found someone had broken a mirror and the windshield of her vehicle and spraypainted her fence. On Nov. 24, her vehicle was spraypainted and all four of its tires were slashed, police said.

In August, McDonald allegedly cut the serpentine belt on her vehicle. Police said a witness identified McDonald as the person spotted near her car about 2 a.m.

Aug. 3, and security camera footage allegedly caught images of a white Saturn car pulling in and out of the apartment complex.

Police noted that McDonald drives a 2004 Saturn sedan like the one depicted on video.

Police said McDonald still had a key to the woman’s vehicle and was able to open it up and pop the hood. The footage showed a man matching McDonald use some sort of tool to mess around in the engine area, police said.

McDonald was also spotted sitting in his car outside the woman’s workplace, watching her go to work in the morning, police allege.

Police said the woman’s license plate was stolen from her vehicle three times.

In October, the cable to the woman’s satellite dish was cut outside her home.

On Nov. 3, the woman took her dog into the backyard and it wandered toward the neighbor’s yard. She saw someone hiding before the man quickly walked away. After she got her dog on a leash and walked back inside, she returned and again saw a man. He walked off when she asked him if she could help him. Once inside, she spotted a white sedan drive slowly down the alley, police noted in the charges.

In November, the woman received text messages in which the sender indicated he knew there was someone else with her in her house and they were upstairs, police added.

On Nov. 20, video from a camera captured a man matching McDonald using what appeared to be a cordless drill to drill four holes into the radiator of her vehicle and on Nov. 25, a man wearing a jacket the woman recognized as belonging to McDonald smashed out the passenger side window.

It was then that she discovered the black box attached to the bumper.

In all, the woman reported 13 incidents to Altoona police related to McDonald’s suspected stalking and thefts.

Bail was set for McDonald on Tuesday morning by Magisterial District Judge Ben Jones at $50,000 cash, and he remains in Blair County Prison. A preliminary hearing is scheduled for Dec. 18 at Central Court.