The first explosion targeted moderate Islamic cleric Dahiru Bauchi while the second one targeted senior opposition leader Muhammadu Buhari, a BBC reporter in the city says. Both escaped unhurt.
There are body parts and damaged cars on the busy Alkali Road in the city centre where the bomb targeting Mr Bauchi exploded, reports the BBC's Abdullahi Kaura Abubakar from the scene.
Kaduna Police chief Shehu Umar said at least 25 people were killed in that blast, apparently caused by a suicide bomber.
Another 15 were killed in the second blast, he said.
Mr Bauchi had completed a preaching session in the nearby Murtala Muhammed square, and was driving through the area in an open-roofed vehicle, greeting well-wishers when he was targeted.
It was revealed that followers of the renowned cleric have reacted angrily, throwing stones at the security forces and accusing them of failing to protect Nigerians, our reporter says; the security forces retaliated by firing tear gas.
About 90 minutes after the first attack, a second explosion ripped through the crowded Kawo area, targeting the motorcade of Gen Buhari, a former military ruler of Nigeria and a senior member of the All Progressive Congress opposition party.
Information given by BBC's reporters says gunmen rammed a vehicle into his convoy, firing shots at it, as a result, two of Gen Buhari's bodyguards were slightly wounded in the attack.
About 90 minutes after the first attack, a second explosion ripped through the crowded Kawo area, targeting the motorcade of Gen Buhari, a former military ruler of Nigeria and a senior member of the All Progressive Congress opposition party.
Information given by BBC's reporters says gunmen rammed a vehicle into his convoy, firing shots at it, as a result, two of Gen Buhari's bodyguards were slightly wounded in the attack.
