Kyrgyzstan and Tajikistan agreed what they called a complete ceasefire on Saturday after reports of fresh shooting and troop build-ups in the aftermath of border clashes earlier this week that killed 49 people. 

The heads of the countries' state security bodies announced the agreement in a joint briefing in Kyrgyzstan hours after Kyrgyzstan's border guard service said Tajik troops opened fire on Kyrgyz vehicles on their side of the border. 

The presidents of the two Central Asian nations also spoke on the phone on Saturday to discuss further steps, their offices said. 

"The tragedy that happened in the border area must never happen again," Saimumin Yatiyev, head of Tajikistan's State National Security Committee, said as he stood next to his Kyrgyz counterpart Kamchybek Tashiyev. 

Russian Foreign Minister Sergei Lavrov spoke by phone with his counterparts in both countries, urging them to stick to the ceasefire agreement, the Russian Foreign Ministry said. 

Kyrgyzstan and Tajikistan, which are former Soviet republics, host Russian military bases and consider Moscow a strategic ally. 

The clashes broke out this week along the frontier between Tajikistan's Sughd province and Kyrgyzstan's southern Batken province because of a dispute over a reservoir and pump, claimed by both sides, on the Isfara River. 

Villagers from opposing sides hurled rocks at each other and border guards joined the fray with guns, mortars and even, according to Kyrgyz border guards, a Tajik attack helicopter. 

At least one Kyrgyz border outpost and a number of houses on both sides were set ablaze and Kyrgyzstan said it had evacuated thousands of people from the area. 

"Eight houses that stood next to mine have been destroyed. How am I going to return there?" said Maria Ismanova, a resident of the Ak Sai village who along with many others has been evacuated to the city of Batken. 

Kyrgyz authorities reported 34 people killed, all but three of them civilians, and 132 wounded. Local government sources in Tajikistan said 15 people had been killed on its side, including six border guards and one policeman. 

The area where the clashes broke out contains a road which connects the Tajik exclave of Vorukh to the mainland. Another road which crosses a disputed border patch is the only link between Kyrgyzstan's Leilek district and the rest of the country. 

While small-scale disputes are frequent along the poorly demarcated border, they rarely escalate to the extent seen this week. Hundreds of people have rallied across both countries expressing desire to travel to the conflict zone and, in some cases demanding weapons from their governments. 

"We are almost certain that this was a deliberate action by the Tajik leadership," said Kamchybek Dosmatov from the village of Arka near the border. 

"I understand that the politicians of Tajikistan are more interested in this conflict. Ordinary people, like us, have become victims."