ABOARD AIR FORCE ONE (AP) - White House spokesman Robert Gibbs says the "systematic targeting" of journalists in Egypt is unacceptable, and says those detained must be freed.

Gibbs says the world is watching the strife in Egypt, and called on the government there to ensure that peaceful protests can take place. He says the time for transition is now, but wouldn't say whether President Hosni Mubarak should step down immediately.

Supporters and opponents of Mubarak have clashed in the streets following his announcements that he would not run for office again, but would stay in power until elections were held. Foreign journalists were beaten with sticks and fists by pro-government mobs and dozens were reported detained by security forces.

Gibbs spoke to reporters traveling with President Barack Obama to Pennsylvania.

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