The main point I want to highlight here is that the only way the attacker got inside is because he was let in! Now I live in an apartment and have seen this same thing happen. It is quite common. People think they are being helpful by holding open the security doors for people.
DON'T DO IT!!!
Even if they look nice and friendly, do not let people inside the building. If you have to, just explain that for security reasons, you would like them to use their key or security device to get in. If they are a resident they will understand and probably be satisfied that other residents are not letting strangers inside the building. Whatever, just don't give people free access inside. Be rude if you need to!
Security is one of the main benefits to living in an apartment complex. Do not jeopardise this and let unknown people gain access. Even if they do not attack you, they may attack someone else and it will be your fault. It is a simple little thing but it is quite important.
Do not let people follow you into your apartment building!!!
The full news story can be read at the following link,
See the news story here.
It is a very sad story that offers a reminder to all of us.