The United States on Monday dismissed demands by the Syrian regime that rebels provide written guarantees that they would lay down arms as a stalling tactic.
Syria was supposed to start pulling troops from towns and cities by Tuesday, paving the way for a cease-fire. President Bashar Assad over the weekend demanded written guarantees from his foes that they would stop fighting and lay down arms.
"This is just another way to stall for time," Victoria Nuland, U.S. State Department spokesperson, told reporters.
The State Department also said that instead of abating, the conflict in Syria had worsened. It said the Syrian government appeared to have little commitment to the plan negotiated by former U.N. chief Kofi Annan.
The Obama administration expressed its outrage, saying the cross-border attack coupled with incidents elsewhere bodes ill for a U.N.-brokered plan to end the violence.
"We strongly condemn any attack by the Syrian regime on refugees in bordering countries and were absolutely outraged by today's report," Nuland said Monday. "We join the Turkish government in calling for the Syrian regime to immediately cease fire."
"We certainly have seen no signs yet of the Assad regime abiding by its commitments," White House press secretary Jay Carney said.
U.N. Secretary-General Ban Ki-moon said he "deplores" the attacks.
There have been similar cross-border attacks into Lebanon, although Monday's shooting was believed to be the first inside Turkey.
Syrian soldiers shot dead a cameraman working for Lebanon's Al-Jadeed television channel on Monday near the border between the two countries, the television channel said.
It said cameraman Ali Shaaban was on the Lebanese side of the frontier, in the northern Lebanese region of Wadi Khaled, when soldiers opened fire on a car carrying the Al-Jadeed crew.
Nuland said there was no sign the Syrian government was removing heavy weaponry from populated areas as called for in the Annan plan.
"We see no indication that it is preparing to do so. It's done some moving around of its tanks and artillery, but only so that it can use them in other places."
"We're going to wait till tomorrow; the deadline is tomorrow," she said. "But based on what we're seeing today, we are not hopeful."
On Monday, opposition activists told Reuters that the Syrian army's bombardment has killed at least 115 people in the northern province of Idlib in the last two days, and troops also rounded up and shot 35 men during military operations in the region.
The activists reports, like others from inside Syria, could not be independently verified because Syria restricts access for foreign reporters.
The Associated Press and Reuters contributed to this report.
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