"NGO staff advised to avoid area"

Life in Gaza, from the Gaza NGO Safety Office:

18 DEC, 0900hrs: Massive demos. will be organized at 1000hrs near UNSCO office, GC, in support of Pal. prisoners. NGO staff advised to avoid the area.

20 DEC, 1000hrs: A sit-in will be organized at 1100hrs in front of UNSCO office, GC. NGO staff advised to avoid the area.

26 DEC, 0900hrs: Palestinian prisoners Association will organize a demo. at 1100hrs in front of UNDP office in GC in support of Pal. prisoners. NGO staff advised to avoid the area.

30 DEC, 1100hrs: A demo. is to be organized in front of UNSCO office, GC, in solidarity with Pal. prisoners. NGO staff advised to avoid area.

31 DEC, 0845hrs: Islamic Jihad will organize a demo. on 1000hrs starting from Palestine Square through Omar Al Mokhtar Street toward ICRC office, GC, in support of Pal. prisoners. NGO staff advised to avoid the area.

31 DEC, 1100hrs: Fatah supporters are holding a demo. starting from Al Azhar University toward Al Saraya compound, GC. NGO staff advised to avoid the area.

If the protests are so peaceful, what are the NGO staff - people who are there to help Gazans - afraid of?