Egypt's press syndicate condemned on Monday what it described as "harassment attempts" by "regime supporters" to storm its headquarters in downtown Cairo.
"Some people dressed like central security forces tried to storm the syndicate headquarters," the syndicate said in a statement, adding that the assailants "were let through by police even though all roads around the syndicate were locked down in order to prevent protests."
It is unclear whether the assailants were members of police forces.
"The syndicate will use its legal rights to defend its properties and journalists from police assaults," the statement added.
Security has been tightened in central Cairo ahead of planned protests on Monday afternoon against the government's recent agreement acknowledging Saudi sovereignty over two Red Sea islands under Egyptian control.
One major protest took place on Monday in Giza's Dokki district and was dispersed by security forces using teargas.
A number of protesters as well as journalists were reportedly arrested.
Earlier in the afternoon, the "Egypt Not For Sale" campaign, which has been mobilising over the agreement in the last two weeks, moved its planned protest site from downtown Cairo to Giza's Dokki in order to dodge police lockdown of the area.