Ma Jiajue killed four people in a row in Dayun dormitory, which caused a sensation throughout the country. Won the second prize in the national physics competition and was also pre-rated as "three good students in the province". The reason why this case has attracted the attention of all walks of life is because the perpetrators are college students, with humble origins and cruel means. According to Ma Jiajue's confession, the cause of the killing was a dispute caused by playing cards.

After an argument with a classmate in the dormitory, Ma Jiajue used a computer to look up information on the Internet, and decided to use a hammer with relatively little bleeding after killing as a crime tool. At the same time, he consulted the geographical information of some provinces and logged on the website of the Ministry of Public Security. The information he found on the computer later became the clue of police investigation.

Ma Jiajue bought a masonry hammer in the second-hand market. According to him, he asked the shopkeeper to cut the wooden handle of the hammer short for convenience. Although he didn't eat the body like Jia, the most abnormal killer in China, he was still guilty. After Ma Jiajue was arrested, he exposed his motive for killing because he couldn't stand the sarcasm of his classmates and friends. Because of a quarrel during playing cards, Ma Jiajue held a grudge against his classmates, and even this psychology gradually turned into murder.

It took a long time from the Ma Jiajue incident to its detection, and the discussion on Ma Jiajue never stopped. It was not until Ma Jiajue was arrested that everyone put down the big stone in their hearts. Ma Jiajue's criminal circumstances are particularly bad, and the consequences of the crime are particularly serious, which constitutes the crime of intentional homicide. Subsequently, Ma Jiajue was taken to the execution ground for execution. The Ma Jiajue incident has aroused social concern about how to deal with college students' dormitories.