An attack by Tuareg rebels in northern Mali killed 20 soldiers and wounded 30, according to the defense minister. The recent siege brings the death toll up for soldiers up to around 40 since fighting broke out five days ago. At least 70 soldiers are being held prisoner. The insurgency now controls two towns, and movement has been detected in at least two other locations, the United Nations said on Thursday. Thousands of Malians have fled the rebel attacks.