Read the following witness statement. What examples of hypothesis have been used?

As I was making my nightly rounds on Monday evening, I noticed a faint light coming from a third floor window of Scope Ltd. It must have been about 11.15 p.m. because I had checked my watch just minutes earlier. As I was proceeding to the main entrance to check for signs of a break-in I witnessed two men running out of the door towards the gate.
Both men appeared to be in their mid thirties and were rather tall with short brown hair. They were wearing dirty ripped jeans and black leather jackets. They must have been professionals because they managed to get in and get out of the building without setting off the sophisticated alarm system. I tried to pursue them but was unable to catch them because they got into a black Ford Cortina and drove off in the direction of Tackinton.
About two minutes later I heard a bomb explode and saw flames coming out of the third floor windows. The fire soon spread to other floors, and the whole building was in flames within minutes.
I immediately called the police and the fire brigade who arrived at 11.30.