UPDATE 2-Sectarian violence kills more in Nigeria's Kaduna
* Christian-Muslim clashes sparked by church bombings
* More than 90 people already killed this week
* Pope appeals for end to sectarian attacks and reprisals
* Boko Haram in gun battle with security forces in northeast (Releads with new violence, parliament summons president, military, govt quotes)
By Garba Mohammed and Mike Oboh
KADUNA/ABUJA, June 20 (Reuters) - Deadly violence between Christians and Muslims in Nigeria's Kaduna flared again on Wednesday, adding to the more than 90 deaths in sectarian clashes in the northern city so far this week.
Religiously mixed Kaduna, near the volatile "Middle Belt", where Nigeria's mostly Christian south and largely Muslim north meet, was the scene of a triple church bombing on Sunday that sparked days of revenge killings.
Dispelling earlier hopes that the violence had eased, locals said Christian youths attacked homes in a Muslim area of Kaduna and police shot dead some of the mob.
Resident Rabo Haladu, who spoke to Reuters by telephone, said he saw bodies lying on the ground and the National Emergency Management Agency said there were unconfirmed reports that dozens of people had been killed.
At least 92 people were killed in the tit-for-tat attacks between Muslims and Christians in Kaduna in the last three days, sparked by suicide bombings of three churches on Sunday that killed 19 people and were blamed on Islamist sect Boko Haram.
The group says it is fighting to reinstate an ancient Islamic caliphate in the north of Africa's top oil producer that would impose strict sharia or Islamic law. The insurgents have killed hundreds since launching an uprising in 2009.
The violence has heightened sectarian tensions in Africa's most populous country, which is evenly split between Christians and Muslims, who mostly live peacefully side by side.
President Goodluck Jonathan was criticised by parliament for travelling to a U.N. summit in Brazil instead of staying to deal with the unrest. The lower house voted on Tuesday to summon him for an explanation.
Information Minister Labaran Maku defended Jonathan's decision, telling Reuters on Wednesday the president could "take decisions from anywhere in the world."
"OVERCOME THE MONSTER"
Chief of Defence Staff Olusheyin Petirin and Police Inspector General Muhammad Abubakar travelled to Kaduna to appeal for an end to the sectarian tensions.
"We understand your unique location which makes Kaduna a mini Nigeria," Petirin said. "This is a serious challenge for which all of us must come together and overcome the monster."
Pope Benedict repeated his concerns about sectarian killings, calling for an end to "terrorist attacks" against Christians and warning against reprisals.
Hundreds of kilometres (miles) from Kaduna, Boko Haram insurgents waged gun battles with security forces in the remote northeastern city of Damaturu, near the radical sect's heartland, throughout Tuesday, police chief for the surrounding Yobe state Patrick Egbuniwe told Reuters.
He said 40 people were killed - 34 insurgents and six security personnel.
Police chief Egbuniwe said Damaturu, which has frequently been a focal point for the insurgency since late last year, was calm on Wednesday and that seven suspects had been arrested.
Local Red Cross official Awwal Sani said his organisation was in Kaduna helping collect bodies and treat the wounded, following riots in which Muslim youths fired AK-47 rifles, burned tyres and destroyed a church on Tuesday.
Boko Haram mostly targets security forces or authority figures but in the past year has turned its sites on Christian worshippers, attacking churches in an apparent attempt to stoke a wider sectarian conflict.
It claimed responsibility for church attacks on the first two Sundays of this month. (Additional reporting by Camillus Eboh and Felix Onuah in Abuja; Writing by Tim Cocks and Joe Brock; Editing by Robin Pomeroy)