Kabul, Sep 18 (IANS) A rocket struck this Afghanistan capital hours before polling for the country's new parliament began Saturday, police said.

According to DPA, no one was injured in the incident, which occurred around 4 a.m. (2330 GMT, Friday), said Abdul Zahir, head of the criminal investigative department of Kabul police.

The rocket struck the state-run Radio TV Afghanistan (RTA). The attack on the RTA offices, located next to the US embassy and across the street from NATO headquarters, came amid heightened security concerns ahead of the voting, which the Taliban have said they would disrupt with bombings.

Security forces are already on high alert in the wake of the country's parliamentary election in which nearly 2,500 candidates are competing for 249 seats in the lower house of parliament - Wolesi Jirga.

Foreign embassies and international organisations in Afghanistan have ordered their staff to stay indoors on polling day because of a heightened risk of attacks from the Taliban, Sky News reported.

The is the second parliamentary polls in the country since the fall of the Taliban regime in 2001. The Islamist militants, who were ousted from power by the 2001 US-led invasion, have threatened to disrupt the polls and have called on Afghans to boycott the vote.

The first election last year was marred by several insurgent attacks and frauds. This election is seen as a test for President Hamid Karzai to legitimise his rule in the eyes of the Afghan people. More than 11 million people are registered to vote in the country.