ARGHANDAB (AFP) - Afghan and Nato troops backed by helicopter gunships killed 23 Taliban Wednesday in a huge "clean-up" operation to drive out fighters entrenched in villages near Kandahar. Two Afghan troops also died in the offensive in southern Arghandab district, which was launched after a burst of insurgent activity including a mass jailbreak in Kandahar that embarrassed US-allied President Hamid Karzai. The operation began as Britain announced the deaths elsewhere of four soldiers, one of them reportedly the country's first female casualty in Afghanistan, while two more Nato soldiers were killed in another incident. An AFP reporter saw helicopters swooping low overhead as Canadian armoured vehicles pushed into the centre of the district. A Taliban spokesman told AFP that the movement's fighters - hundreds of whom swarmed into the district on Monday evening - wanted to capture it in order to launch attacks on Kandahar itself. General Carlos Branco, a spokesman for the Nato-led International Security Assistance Force, said more than 1,000 Afghan and Canadian Nato troops were taking part in the operation launched on Wednesday morning. "We're progressing steadily and carefully in order not only to avoid civilian casualties but because of the potential threat from possible IEDs (improvised explosive devices)," Branco told AFP. An Afghan Defence Ministry statement said that a group of Taliban was "targeted by Nato air force" in Ta-been village in Arghandab, killing 20 "local and foreign terrorists", while three more rebels were shot dead elsewhere in the district. Two soldiers were also killed in the operation, the Ministry said. Branco confirmed that military helicopters had "engaged" the rebels but said no fixed-wing aircraft had dropped bombs. A civilian NATO spokesman, Mark Laity, said that there had been only "minor" clashes with the militants but added that "we've inflicted casualties on the insurgents during these exchanges." A self-styled Taliban commander called Mullah Sayed Ahmad, claiming to be calling from Arghandab, told AFP that there had been "very heavy fighting going on and the Nato helicopters also fired machine guns into our positions." Taliban spokesman Yousuf Ahmadi vowed fierce resistance. "We will use Arghandab for specific attacks with mortars and cannons on targets in Kandahar city. We have also planned a suicide attack which will be carried out in Kandahar," he told AFP by telephone from an unknown location. The operation has forced around 1,500 families to leave their homes and abandon crops that were ready for harvest, said Ahmad Wali Karzai, the head of Kandahar provincial council and a brother of President Karzai. Meanwhile, Taliban spokesman Ahmadi claimed responsibility for a bomb blast in neighbouring Helmand province on Tuesday that the Defence Ministry in London said killed four British troops, including one from the Intelligence Corps. Another two ISAF soldiers died and 10 were wounded during a patrol in eastern Paktika province on Wednesday, the force said in a separate statement.