Complex sentence: Halder held off police and SWAT officers for over seven hours in sniper-like gun battles, while approximately 100 people hid in offices and closets until they were rescued by police.
Split into simpler sentences: Halder held off police and SWAT officers for more than seven hours in sniper-like gun battles. Approximately 100 people hid in offices and closets of the building until being rescued by police.