LONDON: Long-term progress in reducing the number of landmine casualties was reversed last year, and rebel groups used the mines in 10 countries, the largest number since 2006, researchers said on Thursday. Non-state groups were still using the deadly devices in the 12 months to October 2015 in Colombia, Libya, Myanmar, Pakistan, Syria and Yemen, and in Afghanistan, where there was a sharp increase in casualties from improvised explosive devices (IEDs). Landmines were also used by rebels in three countries - Iraq, Tunisia and Ukraine - where they were not used last year, and by three states: Myanmar, Syria and North Korea. 'While the world has made great progress, the past year has seen disturbing steps backward in terms of new use of and casualties from landmines,' said Jeff Abramson, editor of the study, which was carried out by the International Campaign to Ban Landmines, a lobby group. A total of 3,678 people were killed or wounded by landmines over the last year, about 10 per day. This is up from 3,308 in 2013 but far lower than in 1999, the year a major treaty came into force, when there were around 25 casualties each day. The true figure is likely to be higher than the one recorded, but the drop is still highly significant because recording has improved over time, Thursday's report said. The vast majority - about 80 percent - of reported casualties were civilians. 'The new use of antipersonnel mines by non-state armed groups in ... Ukraine and Yemen, and the continuing large-scale use of victim-activated IEDs in Afghanistan and Iraq, are particularly worrisome,' said Mark Hiznay, senior researcher at Human Rights Watch. New landmines were laid in only a small minority of countries, but existing ones are still present in 57 nations. Mozambique declared itself mine-free in September, the 28th country to do so since 1999. At least 200 square kilometres of mined areas worldwide were reported cleared last year, most of them in Afghanistan, Cambodia and Croatia, a slight increase from 2013. The 1999 Ottawa Convention prohibits the use, stockpiling, production and transfer of anti-personnel landmines. While backed by most countries, the treaty has not been endorsed by the United States, Russia, China and India.