Fighting Islamic State in Libya

Fighters of Libyan forces allied with the U.N.-backed government fire a rocket at Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government runs for cover during a battle with Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government fires a shell with Soviet made T-55 tank at Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government fires a rife at Islamic State fighters during a battle in Sirte. REUTERS/Goran Tomasevic

Pieces of bricks fly off the wall as Islamic State fighters open fire at Libyan forces allied with the U.N.-backed government during a battle in Sirte. REUTERS/Goran Tomasevic

Fighters of Libyan forces allied with the U.N.-backed rest on a beach before they fire a shell with Soviet made T-55 tank at Islamic State fighters from a beach in Sirte. REUTERS/Goran Tomasevic

Libyan forces allied with the U.N.-backed government fire weapons during a battle with IS fighters in Sirte. REUTERS/Goran Tomasevic

Fighters of Libyan forces allied with the U.N.-backed government move towards Islamic State fighters positions during a battle in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government looks through a hole in a wall as a self-propelled artillery gun fires at Islamic State fighters during a battle in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government runs for cover with another fighter while carrying a wounded fighter during a battle with Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

Fighters of Libyan forces allied with the U.N.-backed government fire weapons at Islamic State fighters during a battle in Sirte. REUTERS/Goran Tomasevic

Libyan forces allied with the U.N.-backed government fire a 122 MM artillery towards Islamic State fighters positions in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government uses a compass to adjust the line of fire for a 81 mm mortar in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government fires a 81 mm mortar round in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government prays in front of his sniper rifle during a battle with Islamic States fighters in Sirte. REUTERS/Goran Tomasevic

Libyan forces allied with the U.N.-backed government fire weapons during a battle with IS fighters in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government fires a weapon during a battle with IS fighters in Sirte. REUTERS/Goran Tomasevic

Fighters of Libyan forces allied with the U.N.-backed government stand in a house during a battle with IS fighters in Sirte. REUTERS/Goran Tomasevic

Libyan forces allied with the U.N.-backed government fire weapons during a battle with IS fighters in Sirte. REUTERS/Goran Tomasevic

Libyan forces allied with the U.N.-backed government fire weapons during a battle with Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

Libyan forces allied with the U.N.-backed government look at Islamic State fighters' positions in Sirte. REUTERS/Goran Tomasevic

Libyan forces allied with the U.N.-backed government fire weapons at Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

Libyan forces allied with the U.N.-backed government look at the positions of Islamic States fighters in the West part of Sirte. REUTERS/Goran Tomasevic

A wounded fighter of Libyan forces allied with the U.N.-backed government runs for cover during a battle with Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government gestures after other fighters fire artillery at Islamic State fighters during a battle in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government shows a disarmed antipersonnel mine planted by Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

Fighters of Libyan forces allied with the U.N.-backed government fire a rocket at Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government carries a wounded fighter during a battle with Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

Fighters of Libyan forces allied with the U.N.-backed government run for cover during a battle with Islamic State fighters in Sirte. REUTERS/Goran Tomasevic

A fighter of Libyan forces allied with the U.N.-backed government carries a 122 mm tank shell on top of a Soviet made T-55 in Sirte. REUTERS/Goran Tomasevic