A former college soccer star has been arrested for murdering his little brother and his cat at a luxurious apartment building in New Jersey. Matthew Hertgen, 31, was charged with first-degree murder, various weapons offenses and animal cruelty for killing his 26-year-old brother Joseph Hertgen. The Hertgen brothers were raised in the quaint coastal town of Toms River by their multi-millionaire tech mogul father David and mom Debra. Princeton Police responded to a 911 call reporting that there was a fire and a dead body within one of the residences inside the Michelle Mews Apartments on Saturday, according to the Mercer County Prosecutor’s Office. When officers responded to the scene, they found Matthew, who was determined to be the caller, in the residence along with the body of the victim and a dead cat. Police believe Matthew - who attended the ritzy private college Wesleyan University - used a knife and a golf club to brutally assault and murder his brother - who worked as a banker after graduating from the University of Michigan. '[The victim] exhibited various injuries including signs of blunt force trauma and lacerations. Joseph was pronounced dead at the scene,' prosecutors said. 'The complaint alleges that Matthew purposely or knowingly engaged in conduct that led to the death of his younger brother and caused the death of a cat that was located within the residence.' The cause and manner of Joseph's death are pending the results of an autopsy - and the motivation for his killing is unknown. The Michelle Mews Apartment complex is a luxurious building within Palmer Square Residences in downtown Princeton - minutes away from the Ivy League University. Current listings for Michelle Mews Apartments go for $6,275 to $6,300 a month, according to its website. Both men were college soccer stars - Matthew played at Wesleyan University from 2011 to 2014 and Joseph played at the University of Michigan from 2016 to 2019. Each of them were standout soccer players at Toms River North High School as well, reported NJ.com. Joseph graduated college in 2020 with a Bachelor's of Business Administration, Accounting and Finance, and was working as an analyst at Locust Point Capital, his LinkedIn stated. The affluent brothers grew up in a four-bed, three-bath mansion in Toms River, New Jersey, which was kitted out with a swimming pool in the backyard. Online records show the home, which is worth an estimated $1.2 million, was sold in 2018. Their father, David Hertgen, is the president and CFO of business internet provider WiLine Networks, according to his LinkedIn. WiLine Networks was founded in 2002 and makes $88 million in revenue, according to RocketReach. Friends and family have shared tributes for Joseph on social media, posting photos and memories of the young man. 'The best of the best. My heart is broken for your family and friends who became family. Fly high Hertgen,' one friend said. 'Absolutely insane. Rip to a great soccer player and person,' said another.