The IDF has blocked roads heading south from Ashkelon around the Gaza Strip border and told residents of Israeli towns and villages to stay indoors over an unspecified “security event.” DEBKAfile: These emergency measures are put in place when a terrorist infiltration is suspected from the Gaza Strip - often through one of the tunnels the IDF is in the process of destroying. So far,the troops fighting inside the enclave have found and are destroying 36 shafts of 15 tunnels, many of them coming out near an Israeli locale.