A massive terrorist bombing tore through a tourist cafe in the bustling heart of Marrakech's old quarter, killing at least 12 foreigners and three Moroccans in the country's deadliest attack in eight years.

At least 23 people were wounded in the Thursday blast a few minutes before noon in Djemma el-Fna square, one of the top attractions in a country that depends heavily on tourism, Moroccan Interior Minister Taib Chergaoui said.

Government spokesman Khalid Naciri said it was too soon to lay blame for what he called a terrorist attack but he noted that Morocco regularly dismantles cells linked to al-Qaida in the Islamic Maghreb and says it has disrupted several plots.

At least eight French citizens were being treated at Marrakech's main Tofail Hospital, along with one Canadian, a British citizen and three Moroccans, emergency room chief Hicham Nejmi said. Others were being treated at a military hospital and a handful in private clinics.