SANA'A/ADEN - Yemen accused Shi'ite rebels on Tuesday of breaching a truce in the north and the country's main southern city was hit by small blasts, testing the government as it strives to maintain stability. Separately, a government official said tests on the remains of five people recovered in northern Yemen this week showed they were not Europeans taken hostage in the north last year. Yemen's supreme security committee said northern rebels were dragging their heels on implementing a ceasefire deal struck with Sana'a in February to end fighting that drew in neighbouring top oil exporter Saudi Arabia. "The (rebels) returned again to some sites after leaving, established new checkpoints, and committed numerous violations and attacks on citizens and some public and private installations," Yemen's state news agency reported the committee as saying. The rebels were also refusing to hand over landmines removed from the conflict zone which were supposed to be destroyed by the state, the agency said. Sana'a came under intense international pressure to end its northern war after a failed attempt by the Yemen-based regional arm of al-Qaeda to blow up a US-bound plane in December. Analysts said the truce agreement between the government and rebels, who belong to the minority Zaydi sect of Shi'ite Islam, was unlikely to last as it does not address the insurgents' complaints of discrimination by Sana'a. On their website, the rebels, known as the Houthis after the family name of their leader, said military units and local officials had entered unhindered a number of northern areas on Monday, including Malahith, Razih and al-Zaher. "These steps come as we confirm that we do not interfere with matters of the local authorities, and that we have never done so and never will," rebels said in a statement posted on Monday.