Fighting has continued in Sanaa, the Yemeni capital, between forces loyal to the president and those allied to an opposition tribal group.
Much of the fighting has happened in the Hasaba district in the northern part of the city, where fighters from the Hashed tribal confederation face off against forces loyal to Ali Abdallah Saleh, the president of Yemen.
According to Mohamed al-Qadhi, a Yemen-based journalist, the government is sending reinforcements to Sanaa, especially to areas near Hasaba.
"I think [the government forces] are preparing for a massive attack in [Hasaba]," al-Qadhi told Al Jazeera. The current crisis began after more than three months of nationwide protests calling for the ouster of Saleh, who has been in power since 1978.
Witnesses said they heard several blasts but were not sure of the cause or damage near the Hasaba district, the focal point of fighting last week that killed at least 115 people and pushed the country closer to civil war.
"There are very powerful explosions. Sounds like missiles or mortars. May God protect us," a Hasaba resident said.
After a lull of several hours, large blasts began shaking northern Sanaa and nearby areas late on Wednesday, residents said. There was no immediate report of casualties or damage.
This week, there have been three main flashpoints in the country - the fighting in the capital, government troops gunning down protesters in Taiz in the south and a battle with fighters in the coastal city of Zinjibar.
Residents also reported overnight fighting near Sanaa airport, which was closed briefly last week during skirmishes between Saleh's forces and opponents within the powerful Hashed tribal confederation, who are led by Sadeq al-Ahmar.
Fourteen soldiers were killed in overnight fighting with the tribesmen, the Defence Ministry website said.
State TV said troops had retaken a number of government buildings seized by tribesmen and found several bodies inside.
Medical officials told Reuters at least five other people had been killed in the recent fighting, which may have entered a new phase with some troops in armoured vehicles joining the opposition, suggesting more military defections from Saleh.
Speaking to reporters, Hillary Clinton, the US secretary of state, said, "If it wasn't obvious before it certainly should be now that [Saleh’s] presence remains a source of great conflict."
Source: Al Jazeera