Nairobi, Kenya (CNN) -- At least 10 people were killed in two explosions Friday in central Nairobi, the Kenya National Disaster Operation Centre said via Twitter.
As many as 76 people were wounded in the blasts at the Gikomba market and on a public minibus, the disaster agency said. Ambulances evacuated 43 injured males and 33 injured females, the Centre said via Twitter.
Two suspects were arrested in connection with the explosions, which were caused by grenades, according to Nairobi Police Commandant Benson Kibuye.
There have been no claims of responsibility in the attack.
Kenyan President Uhuru Kenyatta expressed his sympathy to those affected by the blasts, the Interior Ministry said via Twitter.
The explosions came after the United States, Australia and UK issued travel alerts for the African nation Thursday.
Hundreds of vacationers were evacuated from Kenya the same day in response to the alerts, which warned of a "high threat" of terrorist attacks.
Kenyan authorities described the warnings as "unfriendly acts" and said security remains a top priority.
"Terrorism is not an evil that was born in Kenya, terrorism is a world wide phenomenon," the Kenyan President said in his state of the union address. As he delivered that speech Friday, the blasts rocked the central part of the capital.
The Kenyan military crossed into Somalia in 2011 to battle the terrorist group Al-Shabaab, which it blamed for kidnapping tourists in the coastal region. In retaliation, the terrorist group has launched a spate of attacks, including targeting bustling bus stations with grenades.
Last year, militants stormed the Westgate Mall in Nairobi and held shoppers under siege for days. At least 67 people were killed.
CNN's Azadeh Ansari reported and wrote from Atlanta. CNN's Pierre Meilhan reported from Atlanta. Journalist Lucy Wamweya reported from Nairobi. CNN's Faith Karimi and Lindsay Isaac also contributed to this report.