Somalia militia Al-Shabaab has warned of an imminent attack in Kenya threatening to bring down tall buildings within two weeks.
The warning was carried by a private intelligence firm, IntelCenter, which said the threat of a huge attack in Kenya over the next six months was high due to increased attacks by Al-Shabaab.
The firm said Al-Shabaab had posted on Wednesday that "something big is coming" within the next two weeks, the Associated Press news agency was quoted as saying.
The militia also said the country would soon "watch your towers coming down."
"Two weeks from now you will weep," the Al-Shabaab threat said, according to AP.
"The towers most likely to be targeted are those housing hotels, especially those frequented by Westerners, government offices, media and prominent corporations.
The building volume of threats and low-level activity indicate that such an attack may be attempted sooner rather than later," AP quoted the Virginia-based IntelCenter as saying.
Kenya police have blamed Al-Shabaab for Monday's blast in downtown Nairobi that left one dead and 35 injured.
The blast ripped through the Assanands House in Nairobi's Moi Avenue at around 1.15pm.
On Wednesday, another explosion hit a small eatery in Wajir, northern Kenya, killing one and injuring three others.
The latest threat by Al-Shabaab is the third such warning.
In October, the militia has said it would target Kenya's tall buildings, just days the country sent troops into Somalia in pursuit of Al-Shabab. A second threat came in December.