Complex sentence: The government responded by intensifying military pressure on the area, however the fighting was costly and government forces sustained heavy casualties throughout 2004 and into early 2005 when the government switched to a tactic of negotiation instead of direct conflict.
Split into simpler sentences: The government responded by intensifying military pressure on the area. However, the fighting was costly: government forces sustained heavy casualties throughout 2004 and into early 2005, when the government switched to a tactic of negotiation instead of direct conflict.