Residents of Qamishli in Syria's al-Hasakeh province have denounced a July 27th "Islamic State of Iraq and the Levant" (ISIL) suicide attack on a densely populated residential area which killed dozens of civilians.

ISIL claimed responsibility for the bombing via its news agency, Amaq.

"The terrorist detonated his [explosives-laden] truck in one of the busiest areas in the city, causing the killing and wounding of a large number of people," said Kurdish Red Crescent administrative staff member Akeed Ibrahim.

More than 50 were killed in the attack and 200 were wounded, Ibrahim told Diyaruna, adding that it will not be possible to determine the exact number of victims until all the rubble has been removed.

Ibrahim, who was in Qamishli to assist with the search and relief efforts, said many of the wounded, particularly children, were in critical condition.

The truck bomb exploded on Mounir Habib street in al-Wusta district, destroying buildings, homes, shops and public facilities, said Rebar Nabo, an Asayesh team leader in the city.

"It is not the first time that the city has been targeted with a suicide bombing," he said. "This was the sixth bombing this year, but it was the most powerful and most heinous."

In response, he added, Asayesh forces are conducting vehicle inspections at the eastern and western entrances to the city using equipment that has detected a large number of car bombs and improvised explosive devices in past months.

The bombing will lead to "increased determination to eradicate the terrorist group that kills no one but civilians", Nabo said.

Terrorism does not exclude anyone

"The first few moments of the explosion were extremely terrifying for residents," said secondary school teacher and Qamishli native Juan Hissou.

"No one knew where the bombing had taken place," he said, adding that it was accompanied by a 15-minute interruption of cell phone service, which exacerbated the confusion.

When residents and the security forces arrived at the scene of the explosion, "panic prevailed" when they saw its magnitude, Hissou said.

Residents attempted to transport the wounded and the dead until the Red Crescent teams arrived, he said, adding that cooking gas cylinder explosions and the outbreak of small fires made the situation difficult.

Tight security measures had been in force due to concerns that ISIL would carry out suicide attacks in retaliation for the losses it is suffering in Manbij and the contraction of the areas under its control, Hissou said.

While he and others in the region consider themselves at war with ISIL, he said, "no one expected its criminality to reach this extent against unarmed civilians".

ISIL "describes the Kurds as apostates who must be killed, yet the blast occurred in front of one of the largest mosques in the city", he said. "How does it consider the Kurds to be apostates when they have a large number of mosques?"

The actions of ISIL are improving relations between Arabs and Kurds "because ISIL’s terrorism does not exclude anyone and does not differentiate between a Kurd and an Arab or an Assyrian, or between Christians and Muslims", he said.

"The strongest proof of that is the fact that everyone is mourning," he added.