Imphal, Feb 16 : No newspaper hit the stands and no local television channels in Manipur aired any news and programmes for the third day on Tuesday as editors and journalists continued to cease work protesting against the attack on a leading Manipuri newspaper office. A Chinese-made grenade was hurled at the office of the "Poknapham" newspaper in the heart of Imphal on Saturday evening but did not detonate. However, police said that if it had blown up, a large number of employees and visitors would have been killed and wounded. Police have not so far made any headway in the ongoing probe, while no extremist outfit has claimed responsibility for the attack. To protest the grenade attack, editors and journalists began a cease work on a call by the All Manipur Working Journalists' Union (AMWJU) and the Editors Guild of Manipur (EGM). Demanding security to the journalists and media offices, a joint delegation of both groups submitted a memorandum to Chief Minister N. Biren Singh who assured to take appropriate action to the demands. Protesting the attack, journalists are holding sit-in demonstrations at Keishampat Leimajam Leikai since Sunday. There had been bomb attacks in some newspaper offices in Imphal in the past, triggering protracted protests from the media community. In some cases, editors and journalists were on strike for weeks as they could not make use of the contradictory statements of some terrorist outfits. A total of 32 newspapers, mostly vernacular, are published daily from Manipur and there are several cable based television channels. /IANS