Israeli troops moved into an area of northern Gaza to expand what they call a security zone around the edge of the enclave, the military said on Friday, days after the government announced plans to seize large areas with an operation in the south. Soldiers carrying out the operation in Shejaia, a suburb east of Gaza City in the north, were letting civilians out via organised routes, the military said in a statement. Israel issued evacuation warnings in the area on Thursday, and hundreds of residents streamed out, some carrying their belongings as they walked, others on donkey carts and bikes or in vans.