The first explosion was carried out by a suicide bomber, according to AP. It was quickly followed by a car bomb near the same area.
Interior Ministry spokesman Sediq Sediqqi confirmed that there are casualties, but said the exact numbers are so far unclear.
Meanwhile, a health official cited by Reuters stated that 23 people had been killed and more than 20 others injured, while TOLO News reported that 27 had been killed and 70 wounded.
@TOLOnews#Kabul - ministry of health confirms at least 40 wounded in Kabul #explosions that targeted convoy of officials leaving parliament offices
The blasts were likely targeting an area which includes government and lawmakers' offices, according to Sediqqi.
@AmichaiStein1#BREAKING: Twin explosion (suicide bomber and car bomb) hit outside parliament offices in #Kabul #Afghanistan; Gunfire heard in the area
TOLO reported that the blasts were targeting a convoy of officials leaving parliament offices.
Taliban spokesman Zabihullah Mujahid said the group was responsible for the attacks.
@TOLOnews#KabulExplosion - eyewitnesses indicate casualty toll of dead and wounded in twin blasts on parliament offices #Kabul could be as high as 50
Earlier on Tuesday, a suicide bomber killed at least seven people in southern Helmand province, according to provincial police chief Gen. Agha Noor Kemtoz. He said the target of that attack was a guesthouse used by a provincial intelligence official.
No one has claimed responsibility for the earlier attack, but the Taliban frequently uses suicide attacks and roadside bombs to target government officials and Afghan security forces.