"The curfew is preventing everyone from moving but some families insist on leaving their homes trying to save themselves. We have been informed than many people have been killed while trying to flee and others have been killed in their homes by militias," said Fatah Ahmed, an Iraq Aid Association spokesman.
"Some displacement camps on the outskirts of Baghdad have received a huge number of people since yesterday and cannot cope. Also, NGOs, because of the curfew and violence, are unable to reach families in need," Ahmed added.
Since 13 June, Mahdi army militants have been targeting Sunni mosques and families. At least six Sunni mosques have been burned in the capital and many civilians killed, said some observers.
"They [Mahdi militants] entered our home, took my father and brother outside and executed them. We are desperate because the bodies cannot be buried because of the curfew. We need help, they shouldn't let this attack bring more violence again to so many desperate families," said Rabab Salim, 21, a Sunni resident of the capital, Baghdad.
"Militants reacted badly to the attack but they shouldn't let this bad action bring more violence to Iraqi families. People are desperate and many have died since yesterday [13 June], including innocent children and women," said Barak Mashadanny, a member of the Iraq Security Consul.
"This will affect the security in Iraq badly. More troops have gone into streets and clashes are continuing between militias and insurgents. Wherever you are you can hear the desperate screaming of women while their husbands are being killed in front of their doors," Mashadanny added.
Ibraheem Saleh, a doctor at the emergency department at Yarmouk hospital, said many injured people were ferried to the hospital and if the situation continued, they would have serious problems because of a lack of emergency materials, and called on local NGOs for help.
"We urge fighters to stop before chaos in the Iraq health system unfolds. Innocent people are coming to get treatment for their injuries, including children. There have been dozens since yesterday," Saleh added.
Since 13 June, the Iraqi police have released many reports about bodies found handcuffed, blindfolded and riddled with bullets in various locations, many with signs of torture.
"Since yesterday, more than 40 bodies were found and it doesn't include those killed inside or in the doors of their homes. There might be dozens more," said Lt Col Ali Hazeem, senior officer in the Ministry of Interior.
"We urge all parties to calm down and think before the lives of innocent civilians are lost. We are working seriously to tackle insurgency in Iraq without affecting the life of the local population. Such sectarian violence will just delay the peace in Iraq," Hazeem said.
"We call on all local NGOs to prepare themselves for the possible increase in displacement and try to continue sending convoys to displacement camps as families are without supplies and cannot move. We call on government and all parties to afford aid workers protection during their work as they are just trying to save lives," said Ahmed of Iraq Aid.