A powerful Taliban suicide bombing tore through central Kabul on Tuesday (April 19), triggering a heavy firefight in a densely packed neighbourhood, a week after the Taliban announced the start of their annual spring offensive. The Taliban claimed responsibility for the attack near the Afghan intelligence agency office, which sent clouds of acrid smoke billowing in the sky and rattled windows several miles away. It was not immediately known if there were any casualties from the assault, which marks the first major Taliban attack in Kabul since the insurgents launched this year's fighting season. 'The first blast was carried out by a suicide bomber in a car and possibly one or two bombers are still resisting,' interior ministry spokesman Sediq Sediqqi told AFP. 'The scene of the attack has been completely cordoned off by Afghan security forces.' Taliban spokesman Zabihullah Mujahid claimed their fighters had managed to enter the office of the National Directorate of Security, the main Afghan spy agency. Afghan officials did not confirm that claim but intense gun battles could be heard near the NDS compound. The Taliban are generally known to exaggerate battlefield claims. 'Today's terrorist attack near Puli Mahmood Khan area of Kabul city demonstrates the clear defeat of the enemy in the face-to-face fight against Afghan security forces,' the Afghan presidential palace said in a statement on Twitter..