Syria crisis: 'Nearly 200 lives lost' in last two days
Almost 200 people have died in two days of clashes in Syria, activists say, as the violence there intensifies.
Two activist groups put Tuesday's toll at 84 - the majority in Idlib province in the north-west.
Video has emerged of a young boy, whose body was apparently torn in half by shelling in the city of Homs.
The bloodshed comes a day before an advance group of Arab League monitors is due to arrive to oversee the implementation of a peace initiative.
The UN said earlier this month that more than 5,000 people had been killed across Syria since protests against President Bashar al-Assad erupted in March.
Damascus says it is fighting "armed terrorist gangs", who want to destabilise the country.
The BBC's Jim Muir in Beirut says the swelling violence could be Syrian authorities "clearing up unfinished business" ahead of the arrival of the Arab League monitors - or it could be unrelated.
In violence on Monday, activists said as many as 110 people may have died in fighting across the country - including 60-70 army deserters apparently gunned down by machine-gun fire close to a village called Kafrouaid in Idlib province.
Activist groups reported more violence in this region of the Zawiya mountains on Tuesday, with the Local Co-ordination Committees saying 25 people had died close to the same village by heavy machine-gun fire and shelling.
Our correspondent says reports suggest security services are acting against army deserters and civilians trapped in a valley.
Many of the towns and cities in Idlib are without internet and mobile phone connections, and some towns are without electricity, the LCC says.
In addition on Tuesday, it says, another 34 people died in Idlib province, 14 in Homs, and 11 elsewhere - bringing the total toll to 84. Another activist group reported the same toll.
Toll 'even higher'
But some reports have given much higher death tolls for the recent violence.
The BBC spoke to Wissam Tarif, a well-known activist based in Beirut, who said accounts from hospitals and witnesses suggested 269 people had been killed in Idlib province on Tuesday alone - mostly defecting soldiers but also 93 loyalist soldiers and six civilians.
Because the Arab League had "called on the Syrian army to stop obeying its political leadership... therefore now we see a high number of defections in the army", he said.
In the local town of Jabal al-Zawiya alone, more than 3,000 soldiers had defected, he claimed - and 10,000 had defected across Syria.
The opposition umbrella group the Syrian National Council (SNC), meanwhile, said 250 had died over Monday and Tuesday. It urged the international community to act against the "horrific massacres".
None of the casualty claims has been independently verified, as foreign media are banned from reporting in Syria - but all the activist groups reporting agree that there has been a surge in violence, our correspondent says, with particular concentrations of bloodshed in mountainous parts of Idlib province and the country's third city of Homs.
Video footage emerged on Tuesday, allegedly showing the body of a young boy torn in half in the ruins of two houses hit by army shelling in Homs.
In other developments:
- Syria's air and naval forces conducted live-fire manoeuvres aimed testing their readiness to repulse "any aggression against the homeland," the official Sana news agency reported, with state TV pictures reportedly showing warplanes and helicopters firing missiles at targets in a desert area, as well as surface-to-air missiles hitting targets in the air.
- Sana reported a new decree under which anyone found guilty of distributing weapons "with the aim of committing terrorist acts" would be sentenced to death.
- Pictures supplied to Reuters news agency by activists apparently showed demonstrations hitting the centre of Damascus on Monday and Tuesday.
League officials have said that the first monitors could be in the country as early as Thursday.
This follows the announcement that Damascus had agreed to the observer mission on Monday.
Syrian Foreign Minister Walid Muallem said the country's sovereignty would be protected because the Arab League had agreed to amendments to the deal, which also calls for all violence to be halted, for the withdrawal of troops from the streets, and the release of detainees.
The observers would be "free" in their movements and "under the protection of the Syrian government", Mr Muallem added, but would not be allowed to visit sensitive military sites.
The observers will have a one-month mandate that can be extended by another month if both sides agree.
The leader of the SNC has dismissed the government's decision as "just a ploy".
Activists say that if the government does withdraw the army, many areas will immediately fall out of its control.