ROME, Jan. 14 (Xinhua) -- Civil protection chief Guido Bertolaso on Thursday warned that relief operations will be "much more complicated" in earthquake-hit Haiti than they were after last April's powerful quake in the Italian region of Abruzzo, adding there could be risk of social unrest.

    "Once the initial shock is over, the anger of the population will rise because people will not find the same type of aid and support that we are used in other parts of the world," Bertolaso was quoted as saying by local news agency ANSA.

    Tuesday's earthquake in Haiti "was one of the most devastating in recent history and struck one of the poorest and least organized areas in the world and this will also complicate our efforts."

    Italy is contributing to the international relief operations in Haiti. On Wednesday a military plane brought supplies and an advance team from the civil protection department to take part in rescue efforts. A second Italian plane is expected to arrive in Haitian capital Port-au-Prince on Thursday carrying emergency supplies and a field hospital with volunteer medical staff.

    Italy's civil protection will also set up a permanent mission in Haiti. "We will not be going there to hand out candies but to offer relief through logistical bases which can deal with an emergency which, unfortunately, we ourselves recently experienced," Bertolaso added.

    The Italian Foreign Ministry on Thursday said it had contacted 80 of the 191 Italians listed as residents in quake-hit Haiti, according to news agency AGI.

    However, concerns are very high for two Italians, a man and a woman, who could be among the victims dead in the collapse of a hotel.

    The head of the ministry's special crisis unit, Fabrizio Romano, said that "there is ample reason to be worried because the number of people we have not been able to contact is higher than the number we have."

    Officials in Haiti fear that upwards of 100,000 people may have been killed by Tuesday's catastrophe, which struck with a 7.0 magnitude.