* Boat is latest in string of refugee arrivals
* Gaddafi has vowed to fight till end
TUNIS, June 24 (Reuters) - - Nineteen police and army officers were among a new group of Libyan refugees who arrived in Tunisia by boat this week, the Tunisian news agency TAP reported on Friday.
The boat carrying a total of 49 refugees arrived on Thursday in the port of El Ketef by the Libyan border, the latest in a string of boat arrivals there since the start of an uprising against Libyan leader Muammar Gaddafi four months ago.
Dozens of Libyan officials, including the foreign minister and the top energy official, have fled since February when a revolt began against the 41-year rule of Gaddafi.
Earlier this week TAP quoted three senior army officers who arrived at the same port on Wednesday as saying the death toll from the conflict exceeded 15,000. It did not say how the officers obtained that toll.
Gaddafi has repeatedly vowed on state television broadcasts to fight until the end. His government says its military capability has not been seriously undermined by defections. (Reporting by Tarek Amara in Tunisia; Editing by Mark John and Peter Graff)