Police detained Nepal's former crown prince on Tuesday for firing a gun into the air after an argument with two guests at a restaurant, officials said.
Local police Chief Keshav Adhikari confirmed that Paras Shah had been detained and was being questioned about the incident.
Shah, the only son of deposed King Gyanendra, admitted firing his gun but defended his action, saying he could not bear to hear insults against his family and country.
He said in a statement that two guests at a restaurant at a resort in southern Nepal had made "baseless and provocative remarks against his role and the institution he represented."
Shah said he left the restaurant, returned half an hour later and fired his gun into the air once, without harming anyone or causing damage.
Shah then fled to another resort in Pokhara, 125 miles west of Katmandu, where he was detained.
Local television stations reported that police had taken complete control of the resort.
During his years as crown prince, Shah was often criticized for hard partying and frequent brawling.
Several street protests were held against him, but he has never faced a criminal investigation or charges.
End of the monarchy
Nepal's Constituent Assembly abolished the centuries-old monarchy in 2008. Shah moved to Singapore with his wife and children after suffering a heart attack, , though he returned to Nepal as his wife started a charity to help impoverished women and children there.
Gyanendra assumed the throne in June 2001 after his elder brother, King Birendra, was killed along with his family in a massacre inside the royal palace.
Shah's cousin, Prince Dipendra, allegedly carried out the killings before taking his own life, according to the BBC report.
Shah spoke out on the massacre last year, saying that his cousin was unhappy about several things, including his family's rejection of his choice of bride, a failed arms deal and the decision to end Nepal's absolute monarchy.
A government investigation was ordered into the massacre, in which 10 people died, but the report was inconclusive and left some questions unanswered.
Many Nepalis suspect Gyanendra and Shah were somehow involved in the slayings.
Gyanendra seized absolute power in 2005, but pro-democracy protests in 2006 forced him to give up his authoritarian rule and restore democracy. Two years later, the monarchy was abolished and Nepal was declared a republic.