Newspapers in Kenya report that cabinet ministers received warnings of a possible attack before al-Shabaab gunmen stormed the Westgate shopping centre in Nairobi last Saturday.
Leaked intelligence briefings detailed plans for attacks in Nairobi and Mombasa in September, according to the Daily Nation.
The warnings were first made in January, according to the newspaper, and again from the beginning of September.
Four cabinet ministers and the head of the defence forces were said to have been informed.
Details from a dossier from the National Intelligence Service published in the Standard also suggest that warnings were issued by Israel that there could be attacks between 4 - 28 September. Al-Shabaab stormed the mall on 21 September.
''Those reports started trickling in from late last year. And they were specific with targets including Westgate," an unnamed senior intelligence official told the AFP news agency.
Three days of official mourning came to an end on Friday. The official death toll is 67, but the Red Cross maintains 61 people are still missing.
The BBC reports the head of the National Intelligence Service is due to be questioned by Members of Parliament on Monday.
Arms stockpile on site
Senior security sources have told the BBC that Al-Shabaab rented a shop in the mall before the attack last Saturday.
This gave the gunmen access to service lifts at Westgate enabling them to stockpile weapons and ammunition.