The explosions occurred outside the police headquarters and academy and as such are believed to have been targeted at the police, AFP reports.
A security source told Reuters that seven people were killed in an initial suicide attack and another 35 people died when explosives planted at the police training school went off.
The country’s interior minister, Abderahim Bireme Hamid has confirmed one attack but no further details have been given as regards the incident.
Chad has contributed troops to the fight against Boko Haram and will expectedly house the headquarters of a joint multinational force to be formed against the sect.
Boko Haram, the Nigerian Islamist militant group, in January threatened to attack Chad for joining a multinational force to fight the insurgents. Chad’s government says it has killed hundreds of Boko Haram fighters since deploying its troops in January.
The attack is probably linked to Islamists retaliating for Chad’s involvement in regional counter-terrorism operations, Ryan Cummings, chief analyst on Africa for security consultancy Red24, said by e-mail from Cape Town.