Palestinian President Mahmoud Abbas has placed his security services on high alert after an upsurge in violence in the West Bank and Gaza Strip. Abbas took the decision after gunmen set fire to Hamas offices in Ramallah, the latest incident in an ongoing cycle of tit-for-tat attacks.The Cabinet building and Parliament were also targeted by gunmen. The rampage followed an attack by Hamas fighters on a security installation in Gaza earlier in the day. The two parties have been locked in a spiral of bitter rivalry since January, when Hamas was elected, ousting Fatah from power. A Hamas official, who was abducted earlier in the day by masked gunmen from the compound in Ramallah, was later set free and reunited with his family. And the violence has claimed the political career of the Palestinian tourism minister Joudeh Mourqos who has resigned. He cited the internecine fighting as the reason behind his decision. At the end of a day of violent clashes in the area, thousands of Palestinians took to the streets of Gaza to demonstrate. They marched in support of Hamas and in opposition to Abbas’ Fatah movement. Abbas has met representatives of Hamas and Islamic Jihad in the hope of diffusing the growing tensions in the region.