The National Disaster Operations Centre said one of the blasts occurred near a 14-seater matatu, while a second explosion occurred within the market.
At least 70 people were injured in the attacks and were undergoing treatment at various city hospitals.
Michael Mwangi who was from a meeting at the nearby Solidarity Building told Capital FM News how he narrowly escaped death.
“I had just come from a meeting and I wanted to go town. I was about to get into the ill-fated matatu when I heard the first blast and fell flat on the ground and the second one went off; that is when I managed to gain refuge in the church,” a visibly shaken Mwangi recalled.
At the same time, Peter Ndegwa who owns a shoe stall a few metres from where the blast took place, explained that he and his colleague shrugged off the initial blast as a tyre blast but only sprang into action on hearing the second blast and the ensuing commotion that left some of their colleagues injured.
“My friend and I had taken a break and we were chatting when we heard the blasts. When were turned behind, we saw a cloud of dust and clothes thrown in the air and then the second one went off. It is only when the dust settled that we saw people were injured and we run and tried to help. We put some in private cars to be taken to hospital,” he said.
Joan Anyango, an omena trader with a makeshift stall across the site of the first scene, was still looking for some of her colleagues when Capital FM News spoke to her. She recounted how they had to flee for safety after the first blast.
“We heard the first blast near where we were and the second one followed. All I remember was there was a lot of confusion as people were falling and tripping over each other. I just kept running but after five minutes I realised the explosions had stopped, so I decided to go back and I saw many people were injured… others were not moving.” she said.
Nairobi Police County Commander Benson Kibue who visited the scene said two suspects had been arrested following the blasts. One of the suspects was nabbed by the public and the other by the police.
“Members of public in the area were able to recognise and forcibly arrest one of the suspects. He is now in our custody. There is another one that we have in our facilities, so that is good news for us because we have a lead and we will be able to come up with conclusive information that will be able to charge these terrorists.”
He urged Kenyans to purpose themselves to know the people around them and remain vigilant at all times.
Vincent Kioko who was standing at the nearby PEFA Church when the blasts took place said the explosives were planted in the stalls.
The blasts occurred nearly two weeks after attacks on matatus plying Thika Road.
President Uhuru Kenyatta who was addressing a news conference at State House just before the blasts occurred sent condolences to the families of the dead and wished the injured quick recovery.