BEIRUT -- Opposition fighters fired mortars Friday at a corridor set aside for rebels and residents to leave besieged eastern Aleppo, Russian and Syrian officials said, breaking a "humanitarian pause" by Moscow and wounding two Russian soldiers and a Syrian journalist.
For most of the 10-hour halt in fighting, which was unilaterally announced by Russia, no one had approached the corridors, and webcam video from the Russian Defence Ministry showed no activity. There was no U.N. monitoring of the exit routes.
During similar, previous halts in fighting, rebels and civilians in eastern Aleppo also mostly stayed put, saying international monitors were not involved and there were no guarantees of security for those who left. Some battle-hardened residents believe the government would arrest anyone who comes out through the corridors.
About four hours before the pause expired, Syrian state media said seven mortar shells from the rebel-held territory hit one of the corridors in the northern part of the city.
The two Russians were slightly wounded during the shelling, and they were evacuated, but their lives were not in danger, the Russian Defence Ministry said. A correspondent for a pro-government broadcaster also was wounded by shrapnel, Syrian state TV said.
The government of President Bashar Assad largely abided by the halt. Russia, a staunch ally, has been supporting Syria's fight against the rebels with a campaign of airstrikes as recently as September and October.
The "humanitarian pause" by Russia raised speculation that a major offensive might begin after its expiration at 7 p.m. (1700 GMT; 1 p.m. EDT). There were no immediate reports of any new airstrikes there.
U.N. officials in Geneva would not comment directly on the Russian initiative but reiterated that security conditions were not adequate for bringing aid into eastern Aleppo. The U.N. stepped up calls for a nationwide truce in the civil war, not just in the northern city.
Asked whether the Russian plan offered a window of opportunity for aid convoys, spokesman Jens Laerke of the U.N. Office for the Coordination of Humanitarian Affairs told reporters: "I'm trying my best not to comment on the actual initiative, but to state what the situation is."
Jessy Chahine, a spokeswoman for U.N. Syria envoy Staffan de Mistura, added that anything that helps save lives "is more than welcome."
But she added that de Mistura was against the evacuation of civilians "unless it is voluntary."
Aleppo, Syria's largest city and once its commercial hub, has become one of the biggest theatres of the civil war, where eastern districts have been controlled by rebels opposed to President Bashar Assad and western areas have been controlled by the government. The eastern part has been besieged by pro-government forces since July, and the U.N. estimates that 275,000 people are trapped there.
The previous halt faltered because the Syrian government and Russia refused to allow humanitarian aid into blockaded area. This time, the U.N. was not part of the announcement or the operation of the corridors.
Meanwhile, a rebel offensive began last week on the government-held areas, home to more than 1 million people, including some displaced from the rebel side. A volley of missiles killed 12 civilians Thursday, state media said.
Overnight, the Syrian military dropped leaflets on the eastern side urging residents and rebels to leave during the pause in fighting, and one posted online by activists gave instructions on how to leave safely, with hands raised. Residents also reported getting text messages urging them to get out.
There has been no official word from Russia on what will happen after the halt in hostilities expires. Similar pauses ended last month with no resumption of airstrikes, which Russia said it had halted in eastern Aleppo. Some residents later reported bombardment on the front line with western districts.
On Thursday, a Russian lawmaker told the Interfax news agency that a "purge" of eastern Aleppo would begin if the pause produced no results. President Vladimir Putin urged opposition fighters to leave via the corridors.
Russia's aircraft carrier, the Admiral Kuznetsov, is in the Mediterranean and headed for the Syrian coast. Its presence suggests that Russia may be intending to escalate its assault on the rebels.
A rebel spokesman, Yasser al-Youssef of the Nour el-Din el-Zinki group, said opposition fighters are anticipating a "violent air campaign" in eastern Aleppo.
"The Russians are exerting more pressure on the rebellious people of Aleppo to get them out of the city," al-Youssef told The Associated Press. "This will not happen. Absolutely."
Syrian state TV showed buses parked in one of the corridors waiting for anyone leaving eastern Aleppo. Police and an Islamic cleric also were at the crossing.
No one had used the corridors by midday, the Britain-based Syrian Observatory for Human Rights said, and a Civil Defence volunteer in Aleppo, Ibrahim al-Haj, added that no had left in the early afternoon.
Concern about civilian safety was mounting amid a "looming threat of a resumption and a possible escalation of the fighting" after the humanitarian pause, Amnesty International said.
"The scale of the devastation in eastern Aleppo in recent months has been chilling," said Samah Hadid of Amnesty's Beirut office. "Given the track record of the forces fighting in Aleppo -- particularly government forces -- Amnesty International fears there will be very high civilian casualties as Syrian forces, supported by Russia, escalate attacks in order to seize control of the city."
A temporary pause "is no substitute for unfettered and impartial humanitarian access and ensuring protection of civilians in the longer term," Hadid said.
Armed groups have also put civilians at risk in western districts "from the repeated, unlawful use of imprecise explosive weapons," Hadid added.
Outside the city, warplanes continued to target rebel supply lines in western parts of Aleppo province, according to al-Youssef of the Nour el-Din el-Zinki group.
Missiles were fired on the towns of Urem al-Kubra and Kfar Naha, wounding several people, the Qasioun news agency reported. Video from Urem al-Kubra showed women and children running amid a blanket of white dust and wrecked homes and a grocery store.
Airstrikes also hit the western town of Atareb, about 24 kilometres (15 miles) from the city of Aleppo, killing at least three children, according to the activist site Aleppo Today TV and the Revolutionary Forces of Syria.
- Associated Press writers Albert Aji in Damascus, Syria, Vladimir Isachenkov in Moscow and Jamey Keaten in Geneva contributed.
