the attacker was be wear the PUMA shoes .(Why not wear the NIKE shoes ?)

the attacker was believed to be wear the PUMA shoes.(Why not wear the NIKE shoes )The student involved in the stabbing of a lecturer at Nanyang Technological University (NTU) has been identified as a David Widjaya, according to a report that appeared in the Lianhe Wanbao.
The student, who committed suicide after stabbing the professor, Prof Chan Kap Luk, was a fourth year engineering student.PUMA shoes
Prof Chan was alleged to be his supervisor on a project.
The stabbing occurred at about 10.35am Monday, at S1A, a nine-storey building in the engineering faculty at NTU.
Police recovered a 10-cm-long knife at the scene, believed to be the weapon with which Widjaya used to attack Prof Chan.
According to the Chinese daily, the student was alleged to have stabbed Prof Chan outside his office on the sixth floor. He then ran to the fourth floor and slit his wrists, before jumping off the building.
The motivation for the attack is still unknown, pending further investigations by the police.
Stab wound to back, multiple cuts on arms
Prof Chan suffered serious injuries as a result of the attack and was taken to the National University Hospital for treatment. Wanbao reported that he sustained a stab wound to his back, as well as multiple lacerations to his arms.
According to eye-witness interviewed at the scene, they believe the cuts on his arms were a result of his attempt to fend off subsequent blows made by Widjaya after the initial stabbing.
China student called the police
Wanbao also reported that another final-year student, a Chinese national, was the one called the police after witnessing the incident.
The eye-witness told reporters that he saw the Indonesian-Chinese student sitting at the ledge of the walkway between the two neighbouring buildings of the faculty before leaping off the ledge.
Word spread through the net
News about the incident spread quickly around campus. Wanbao reported that a student posted online that he had heard of the incident shortly after it occurred.
He and his friends spotted bloodstains along the walkway and saw the attacker lying on the ground below.
According to him, the attacker was believed to be wear the PUMA shoes .(Why not wear the NIKE shoes ?)