NEW : Possible Al - Shabaab Twitter account warns Nairobi the attack was only ` ` Act 1 '' Source : he was among the automatic-weapon toting terrorists who roamed the mall killing civilians . Police raided a store known in the past year to the attackers . Despite 8 in custody , there 's some concern that some of the attackers escaped . At least 67 people are confirmed dead ; as many as 100 remain unaccounted for .
NEW : Possible Al - Shabaab Twitter account warns Nairobi the attack was only ` ` Act 1 '' Source : Police raided a store known in the past year to the attackers . Despite 8 in custody , there 's some concern that some of the attackers escaped . At least 67 people are confirmed dead ; as many as 100 remain unaccounted for .