London - U.K. police said Monday they had arrested two teenagers after the latest arson attack on sites including Jewish ones in London, bringing the number of arrests for six incidents to 15.Matt Jukes, deputy commissioner of the Metropolitan Police, said the new arrests came amid a pattern of 'thugs for hire' as the United Kingdom sees 'the pressure of hostile states bearing into our communities.'In parliament, Security Minister Dan Jarvis denounced violence against British Jews as 'an attack on all of us,' pledging to 'do whatever it takes to stop the cowards and the thugs who seek to intimidate our Jewish communities.'