Blasts rang out across the city of Jammu in Indian Kashmir late on Thursday during what Indian military sources said they suspected was a Pakistani drone attack on the second day of clashes between the two neighbours.
Several parts of Jammu and the surrounding towns of Akhnoor, Samba and Kathua came under attack, according to Indian officials.
There was no immediate comment from Pakistan on what appeared to be an escalation in the countries' worst confrontation in more than two decades.
Pakistan’s Defence Minister, Khawaja Muhammad Asif, had earlier said further retaliation was “increasingly certain” after both countries accused each other of launching drone attacks.
India said it hit nine "terrorist infrastructure" sites in Pakistan on Wednesday in retaliation for what it says was a deadly Pakistan-backed attack in Jammu and Kashmir on April 22.
Pakistan says it was not involved and denied that any of the sites hit by India were militant bases. It said it shot down five Indian aircraft on Wednesday, a report the Indian embassy in Beijing dismissed as "misinformation".
Pakistan said earlier on Thursday it shot down 25 drones from India overnight, while India said its air defences had stopped Pakistani drone and missile attacks on military targets.
World powers from the US to Russia and China have called for calm.
The United States expressed confidence that peace talks with Iran would go ahead in Pakistan and a senior Iranian official said Tehran was considering joining, but significant hurdles and uncertainty remained as the end of a ceasefire loomed.
A gunman shot one dead as he opened fire at Mexico's Teotihuacan pyramids on Monday before taking his own life, authorities said, in a rare attack at a major tourist attraction.
Iran is considering attending peace talks with the United States in Pakistan, a senior Iranian official told Reuters on Monday, following moves by Islamabad to end a US blockade of Iran's ports, a major hurdle for Iran to rejoin peace efforts.
Israeli strikes have killed at least five Palestinians in separate incidents in the Gaza Strip on Monday, Palestinian health officials said, while fighters from Hamas clashed with gunmen from an Israeli-backed militia, witnesses said.
President Donald Trump said on Monday he believed a nuclear deal the US is currently negotiating with Iran will be better than a 2015 international agreement to curb Tehran's nuclear programme.
His Highness Sheikh Mohammed bin Rashid Al Maktoum, Vice President and Prime Minister of the UAE and Ruler of Dubai, has reviewed the AED3billion Beach Development Plan to turn Dubai into the world's best city to live in by 2040.
UAE President His Highness Sheikh Mohamed bin Zayed Al Nahyan has reviewed national plans with His Highness Sheikh Saud bin Saqr Al Qasimi, Supreme Council Member and Ruler of Ras Al Khaimah, in a meeting on Tuesday.